victron energy BMV-712 Smart Battery Battery Monitor User Manual
- June 13, 2024
- victron energy
Table of Contents
BMV-712 Smart Battery Battery Monitor
Product Information – BMV-712 Smart Battery Monitor
Manual – BMV-712 Smart
Battery monitor
Rev 12 – 05/2023
Table of Contents
- Safety precautions
- General safety precautions
- Battery safety warnings
- Transport and storage
- Introduction
- Installation
- Configuration
- Setup wizard
- Automatic voltage detection
- How to change settings
- Operation
- Interfacing
- All features and settings
- How to change settings
- Accessing settings via the head unit
- Accessing settings via the VictronConnect app
- Saving, loading and sharing settings in VictronConnect
- Additional settings
- Reset history
- Battery capacity and Peukert exponent
- Technical data
- Technical data
- Appendix
- Dimensions BMV head unit
- Dimensions shunt
Product Usage Instructions
Installation
The BMV-712 Smart Battery Monitor should be installed according
to the manufacturer’s instructions. Please refer to the
installation section of the user manual for detailed instructions
on how to properly install the battery monitor.
Configuration
To configure the BMV-712 Smart Battery Monitor, follow the steps
below:
-
Access the setup wizard by navigating to the setup menu on the
head unit or using the VictronConnect app. -
Enable automatic voltage detection to ensure accurate
readings. -
Change settings as needed using the options provided in the
setup menu.
Operation
Once the BMV-712 Smart Battery Monitor is installed and
configured, it can be used to monitor the battery status. The
monitor will display important information such as battery voltage,
current, state of charge, and more. Refer to the user manual for
detailed instructions on how to interpret and use the information
provided by the battery monitor.
Interfacing
The BMV-712 Smart Battery Monitor can be interfaced with other
devices or systems using the available communication ports. Consult
the user manual for information on how to connect and interface the
battery monitor with external devices.
All Features and Settings
The BMV-712 Smart Battery Monitor offers a range of features and
settings that can be customized according to your needs. These
settings can be accessed via the head unit or the VictronConnect
app. Refer to the user manual for detailed instructions on how to
access, modify, and save these settings.
Battery Capacity and Peukert Exponent
The user manual provides information on how to calculate battery
capacity and the Peukert exponent. This information can be useful
for accurately estimating battery performance and capacity. Refer
to the user manual for detailed instructions on how to perform
these calculations.
Technical Data
For detailed technical specifications of the BMV-712 Smart
Battery Monitor, please refer to the technical data section of the
user manual.
Appendix
The appendix section of the user manual provides additional
information and dimensions of the BMV head unit and shunt. Consult
this section for specific measurements and dimensions.
ENGLISH
Manual – BMV-712 Smart
Battery monitor
Rev 12 – 05/2023
This manual is also available in HTML5.
Manual – BMV-712 Smart
Table of Contents
1. Safety precautions ……………………………………………………………………………………………………. 1
1.1. General safety precautions ……………………………………………………………………………………. 1 1.2.
Battery safety warnings ……………………………………………………………………………………….. 1 1.3. Transport
and storage ………………………………………………………………………………………… 1
2. Introduction …………………………………………………………………………………………………………… 2
2.1. The battery monitor …………………………………………………………………………………………… 2 2.2. Why should
I monitor my battery? …………………………………………………………………………….. 2 2.3. Sizing
…………………………………………………………………………………………………………. 2 2.4. The VictronConnect app
………………………………………………………………………………………. 2 2.5. Accessories
…………………………………………………………………………………………………… 3
3. Installation …………………………………………………………………………………………………………….. 4
3.1. What’s in the box? …………………………………………………………………………………………….. 4 3.2. Mounting
the shunt ……………………………………………………………………………………………. 4 3.3. Mounting the head unit
……………………………………………………………………………………….. 5 3.4. Connections overview
………………………………………………………………………………………… 7 3.5. Basic electrical connections
…………………………………………………………………………………… 7 3.6. Auxiliary electrical connections
……………………………………………………………………………….. 8
3.6.1. Auxiliary connection for monitoring the voltage of a second battery
…………………………………. 8 3.6.2. Auxiliary connection midpoint battery bank monitoring
………………………………………………. 8 3.6.3. Auxiliary connection for temperature monitoring
…………………………………………………….. 9 3.7. Programmable relay
…………………………………………………………………………………………… 9 3.8. Use of alternative shunts
……………………………………………………………………………………. 10 3.9. GX device connection
……………………………………………………………………………………….. 10 3.10. Wiring for use as DC meter
………………………………………………………………………………… 11
4. Configuration ……………………………………………………………………………………………………….. 12
4.1. Setup wizard ………………………………………………………………………………………………… 12 4.2. Automatic
voltage detection …………………………………………………………………………………. 12 4.3. How to change
settings ……………………………………………………………………………………… 13
4.3.1. Settings via the head unit ………………………………………………………………………….. 13 4.3.2. The
VictronConnect app ……………………………………………………………………………. 14 4.4. Update firmware
…………………………………………………………………………………………….. 15 4.5. Make essential settings
……………………………………………………………………………………… 15 4.5.1. Set the battery capacity value
……………………………………………………………………… 15 4.5.2. Set charged voltage value
………………………………………………………………………….. 15 4.5.3. Set state of charge
…………………………………………………………………………………. 16 4.5.4. Set the auxiliary input function
……………………………………………………………………… 16 4.6. Make Lithium settings (if needed)
…………………………………………………………………………… 16 4.7. Configure for use as DC meter
……………………………………………………………………………… 17
5. Operation ……………………………………………………………………………………………………………. 18
5.1. How does the battery monitor work? ………………………………………………………………………… 18 5.2.
Readout overview …………………………………………………………………………………………… 18 5.3. Using the head
unit menus ………………………………………………………………………………….. 19 5.4. Trends
………………………………………………………………………………………………………. 19 5.5. History
………………………………………………………………………………………………………. 20
5.5.1. Accessing historical data via the VictronConnect app ………………………………………………
20 5.5.2. Accessing historical data via the head unit ………………………………………………………….
21 5.5.3. History data ………………………………………………………………………………………… 22 5.6. Alarms
………………………………………………………………………………………………………. 22 5.7. Synchronising the battery
monitor …………………………………………………………………………… 23 5.7.1. Automatic synchronisation
…………………………………………………………………………. 23 5.7.2. Manual synchronisation
……………………………………………………………………………. 23 5.8. Operation as a DC meter
……………………………………………………………………………………. 24
6. Interfacing …………………………………………………………………………………………………………… 25
6.1. VictronConnect app via USB ………………………………………………………………………………… 25 6.2.
Connecting to a GX device and the VRM portal …………………………………………………………….. 25 6.3.
Connecting to VE.Smart networking ………………………………………………………………………… 26 6.4. Custom
integration ………………………………………………………………………………………….. 27
Manual – BMV-712 Smart
7. All features and settings ……………………………………………………………………………………………. 28
7.1. How to change settings ……………………………………………………………………………………… 28 7.1.1.
Accessing settings via the head unit ……………………………………………………………….. 28 7.1.2.
Accessing settings via the VictronConnect app …………………………………………………….. 28 7.1.3.
Saving, loading and sharing settings in VictronConnect ……………………………………………. 28
7.2. Battery settings ……………………………………………………………………………………………… 28 7.2.1. Battery
capacity ……………………………………………………………………………………. 28 7.2.2. Charged voltage
……………………………………………………………………………………. 29 7.2.3. Discharge floor
…………………………………………………………………………………….. 29 7.2.4. Tail current
…………………………………………………………………………………………. 29 7.2.5. Charged detection time
…………………………………………………………………………….. 29 7.2.6. Peukert exponent
………………………………………………………………………………….. 29 7.2.7. Charge efficiency factor
……………………………………………………………………………. 30 7.2.8. Current threshold
…………………………………………………………………………………… 30 7.2.9. Time-to-go averaging period
……………………………………………………………………….. 30 7.2.10. Battery starts synchronised
……………………………………………………………………….. 30 7.2.11. State of charge
……………………………………………………………………………………. 31 7.2.12. Synchronise SoC to 100%
………………………………………………………………………… 31 7.2.13. Zero current calibration
…………………………………………………………………………… 31
7.3. Relay settings ……………………………………………………………………………………………….. 31 7.3.1. Relay
mode ………………………………………………………………………………………… 31 7.3.2. Invert relay
…………………………………………………………………………………………. 32 7.3.3. Relay state
…………………………………………………………………………………………. 32 7.3.4. Relay minimum closed time
………………………………………………………………………… 32 7.3.5. Relay off delay
……………………………………………………………………………………… 32 7.3.6. Low State of Charge (SoC) relay
…………………………………………………………………… 32 7.3.7. Low voltage relay
…………………………………………………………………………………… 33 7.3.8. High voltage relay
………………………………………………………………………………….. 33 7.3.9. Low starter voltage relay
…………………………………………………………………………… 33 7.3.10. High starter voltage relay
…………………………………………………………………………. 33 7.3.11. Low temperature relay
…………………………………………………………………………….. 34 7.3.12. Mid voltage relay
………………………………………………………………………………….. 34
7.4. Alarm settings ……………………………………………………………………………………………….. 34 7.4.1. Alarm
buzzer ……………………………………………………………………………………….. 34 7.4.2. Low SoC alarm settings
……………………………………………………………………………. 34 7.4.3. Low voltage alarm
………………………………………………………………………………….. 35 7.4.4. High voltage alarm
…………………………………………………………………………………. 35 7.4.5. Low starter voltage alarm
………………………………………………………………………….. 35 7.4.6. High starter voltage alarm
………………………………………………………………………….. 36 7.4.7. High temperature alarm
……………………………………………………………………………. 36 7.4.8. Low temperature alarm
…………………………………………………………………………….. 36 7.4.9. Midpoint deviation alarm
…………………………………………………………………………… 36
7.5. Display settings ……………………………………………………………………………………………… 36 7.5.1. Backlight
intensity ………………………………………………………………………………….. 36 7.5.2. Backlight always on
………………………………………………………………………………… 36 7.5.3. Scroll speed
………………………………………………………………………………………… 37 7.5.4. Main voltage display
……………………………………………………………………………….. 37 7.5.5. Current display
…………………………………………………………………………………….. 37 7.5.6. Power display
………………………………………………………………………………………. 37 7.5.7. Consumed Ah display
……………………………………………………………………………… 37 7.5.8. State of charge display
…………………………………………………………………………….. 37 7.5.9. Time-to-go display
………………………………………………………………………………….. 37 7.5.10. Starter voltage display
……………………………………………………………………………. 38 7.5.11. Temperature display
………………………………………………………………………………. 38 7.5.12. Mid-voltage display
……………………………………………………………………………….. 38
7.6. Miscellaneous settings ………………………………………………………………………………………. 39 7.6.1.
Software version …………………………………………………………………………………… 39 7.6.2. Restore defaults
……………………………………………………………………………………. 39 7.6.3. Clear history
……………………………………………………………………………………….. 39 7.6.4. Lock setup
…………………………………………………………………………………………. 39 7.6.5. Shunt current
………………………………………………………………………………………. 40 7.6.6. Shunt voltage
………………………………………………………………………………………. 40 7.6.7. Temperature unit
…………………………………………………………………………………… 40 7.6.8. Temperature coefficient
…………………………………………………………………………….. 40 7.6.9. Aux input
…………………………………………………………………………………………… 40 7.6.10. Battery starts synchronised
……………………………………………………………………….. 40 7.6.11. Bluetooth mode
…………………………………………………………………………………… 41 7.6.12. Monitor Mode
……………………………………………………………………………………… 41
7.7. Additional settings …………………………………………………………………………………………… 41 7.7.1. Reset
history ……………………………………………………………………………………….. 41
Manual – BMV-712 Smart
7.7.2. Reset PIN code …………………………………………………………………………………….. 41 7.7.3. Temperature
unit setting ……………………………………………………………………………. 41 7.7.4. Serial number
………………………………………………………………………………………. 42 7.7.5. Disabling and re-enabling
Bluetooth ……………………………………………………………….. 42 7.7.6. Changing PIN code
………………………………………………………………………………… 42 7.7.7. Custom name
………………………………………………………………………………………. 42 7.7.8. Firmware
…………………………………………………………………………………………… 42 7.7.9. Reset to defaults
…………………………………………………………………………………… 43
8. Battery capacity and Peukert exponent ……………………………………………………………………………. 44
9. Midpoint voltage monitoring ……………………………………………………………………………………….. 46 9.1.
Battery bank and midpoint wiring diagrams …………………………………………………………………. 46 9.1.1.
Connecting and monitoring midpoint in a 24V battery bank ………………………………………… 46
9.1.2. Connecting and monitoring midpoint in a 48V battery bank
………………………………………… 47 9.2. Midpoint deviation calculation
……………………………………………………………………………….. 48 9.3. Setting the alarm level
………………………………………………………………………………………. 48 9.4. Alarm delay
…………………………………………………………………………………………………. 48 9.5. What to do in case of an alarm
during charging …………………………………………………………….. 48 9.6. What to do in case of an
alarm during discharging ………………………………………………………….. 49 9.7. The Battery Balancer
………………………………………………………………………………………… 49
10. Troubleshooting …………………………………………………………………………………………………… 50 10.1.
Functionality issues ………………………………………………………………………………………… 50 10.1.1. Unit is
dead ……………………………………………………………………………………….. 50 10.1.2. Auxiliary port not working
…………………………………………………………………………. 50 10.1.3. Unable to change VictronConnect
settings ……………………………………………………….. 50 10.2. Connection issues
…………………………………………………………………………………………. 50 10.2.1. Cannot connect via Bluetooth
…………………………………………………………………….. 50 10.2.2. PIN code lost
……………………………………………………………………………………… 51 10.3. Incorrect readings
………………………………………………………………………………………….. 51 10.3.1. Charge and discharge current
are inverted ……………………………………………………….. 51 10.3.2. Incomplete current reading
……………………………………………………………………….. 51 10.3.3. There is a current reading while no
current flows …………………………………………………. 51 10.3.4. Incorrect state of charge
reading …………………………………………………………………. 52 10.3.5. State of charge is missing
………………………………………………………………………… 52 10.3.6. State of charge does not reach 100%
…………………………………………………………….. 52 10.3.7. State of charge always shows 100%
……………………………………………………………… 53 10.3.8. State of charge does not increase fast
enough or too fast when charging ………………………… 53 10.3.9. Incorrect battery
voltage reading ………………………………………………………………….. 53 10.3.10. Incorrect auxillary
battery voltage reading ……………………………………………………….. 53 10.3.11. Synchronisation
issues ………………………………………………………………………….. 53
11. Technical data ……………………………………………………………………………………………………… 54 11.1. Technical
data ……………………………………………………………………………………………… 54
12. Appendix …………………………………………………………………………………………………………… 55 12.1. Dimensions
BMV head unit ………………………………………………………………………………… 55 12.2. Dimensions shunt
………………………………………………………………………………………….. 56
1. Safety precautions
Manual – BMV-712 Smart
1.1. General safety precautions
Read this manual carefully. It contains important instructions that must be
followed during installation, operation and maintenance. Save these
instructions for future reference on operation and maintenance.
1.2. Battery safety warnings
Working in the vicinity of a lead acid battery is dangerous. Batteries can
generate explosive gases during operation. Never smoke or allow a spark or
flame in the vicinity of a battery. Provide sufficient ventilation around the
battery. Wear eye and clothing protection. Avoid touching eyes while working
near batteries. Wash your hands when done. If battery acid contacts skin or
clothing, wash them immediately with soap and water. If acid enters an eye,
immediately flood the eye with running cold water for at least 15 minutes and
get medical attention immediately. Be careful when using metal tools in the
vicinity of batteries. Dropping a metal tool onto a battery might cause a
short circuit and possibly an explosion. Remove personal metal items such as
rings, bracelets, necklaces, and watches when working with a battery. A
battery can produce a short circuit current high enough to melt objects such
as rings, causing severe burns.
1.3. Transport and storage
Store this product in a dry environment. Store this product in temperatures
between -40°C and +60°C.
Page 1
Safety precautions
Manual – BMV-712 Smart
2. Introduction
2.1. The battery monitor
The BMV-712 Smart is a battery monitor. It measures battery voltage and
current. Based on these measurements, it calculates the battery’s state of
charge and the time to go. It also keeps track of historical data, such as
deepest discharge, average discharge and the number of charge and discharge
cycles. All monitored battery parameters can be read out, and settings can be
changed via the display and the four buttons. A connection with the
VictronConnect app is possible via Bluetooth or USB. The VictronConnect app
can be used to read out all monitored battery parameters or to change
settings. To connect via USB, an optional VE.Direct to USB interface is
needed. If the battery monitor is connected to a GX device, such as the Cerbo
GX or the ColorControl GX, the battery can be monitored locally with the GX
device or remotely via the VRM portal. The auxiliary input can be used to
monitor the voltage of a second battery or the midpoint of a battery bank. The
auxiliary input can also be used for battery temperature monitoring, together
with the optional Temperature sensor for BMV. When connected to other Victron
products via VE.Smart networking, the battery monitor can provide real-time
battery data such as battery temperature, voltage and current via Bluetooth
for use by Victron solar chargers and select AC chargers.
2.2. Why should I monitor my battery?
Batteries are used in a wide variety of applications, mostly to store energy
for later use. But how much energy is stored in the battery? No one can tell
by just looking at it. The service life of batteries depends on many factors.
Battery life may be shortened by under-charging, over-charging, excessively
deep discharges, excessive charge or discharge currents, and by high ambient
temperature. Monitoring the battery with a battery monitor will give important
feedback to the user so that remedial measures can be taken when necessary.
Doing this will extend battery life and the battery monitor will quickly pay
for itself.
2.3. Sizing
The battery monitor is available in one size; it has a 500A shunt. However, it
is possible to use the battery monitor with larger shunts all the way up to
9999A. Larger shunts are not included. For 1000A, 2000A or 6000A shunts see
the Shunt product page.
2.4. The VictronConnect app
The VictronConnect app can be used to monitor and configure the battery
monitor. Note that configuring the battery monitor using the VictronConnect
app is easier than configuring using the battery monitor head unit. The
VictronConnect app can connect to the battery monitor via: · Bluetooth.
· USB, using the optional VE.Direct to USB interface.
· Remotely via a GX device and the VRM portal.
The VictronConnect app is available for the following platforms: · Android.
· Apple iOS (Note that USB is not supported, it is only possible to connect
via Bluetooth).
· macOs.
· Windows (Note that Bluetooth is not supported, it is only possible to
connect via USB).
The VictronConnect app can be downloaded from app stores or from the
VictronConnect product page or scan the below QR code.
Page 2
Introduction
Manual – BMV-712 Smart
2.5. Accessories
These optional parts might be needed depending on your setup: · Temperature
sensor for BMV – to measure the battery temperature. · GX Device, such as a
Cerbo GX – for system and/or remote monitoring. · VE.Direct cable – to connect
the battery monitor to a GX device. · VE.Direct to USB interface – to connect
to the battery monitor via USB to a GX device or to the VictronConnect app. ·
Wall mount enclosure for BMV or MPPT Control – use in case panel mounting of
the battery monitor head unit is not possible. · Wall mount enclosure for BMV
and Color Control GX – use to wall mount the battery monitor head unit
together with a Color
Control GX in the same enclosure. · RJ12 UTP cable – use in case the supplied
10m (32ft) RJ12 cable (the cable between the shunt and the head unit) is too
long
or too short. These cables are available in a variety of lengths of 30cm up to
30 meters (1ft up to 98ft).
Page 3
Introduction
3. Installation
3.1. What’s in the box?
Manual – BMV-712 Smart
BMV-712 Smart head unit together with attachment sleeve.
500A shunt. Two 1.5m (59″) red cables with a 1A fuse. 10m (33ft) RJ12 UTP cable.
Square face plate together with an attachment flange.
Bag with 4 small screws.
Quick installation guide.
Spare serial number sticker.
3.2. Mounting the shunt
The shunt has an IP21 rating; this means that the shunt is not waterproof and
has to be mounted in a dry location.
The shunt has two 5.5 mm holes for mounting purposes; these are located in the
base of the shunt. The holes can be used to screw or bolt the shunt onto a
hard surface (note that these screws are not included).
Page 4
Installation
Manual – BMV-712 Smart For the exact location of the mounting holes see the
dimension drawing [56] in the appendix of this manual.
Top view shunt indicating mounting holes and side view shunt indicating the
mounting method.
3.3. Mounting the head unit
The head unit can be mounted in a variety of ways: A. Panel mounting, the head
unit is secured at the back of a panel. B. Panel mounting, the head unit is
secured at the front of the panel. C. Wall mounting, using an optional wall
mounting enclosure.
1
2
3
Mounting method A.
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Installation
Manual – BMV-712 Smart
1
2
3
4
5
6
Mounting method B.
1
2
3
Mounting method C.
For the full wall mounting instructions, see the wall mounting installation
manuals on the Wall mount enclosure for BMV or MPPT Control or Wall mount
enclosure for BMV and Color Control GX product pages.
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Installation
3.4. Connections overview
Manual – BMV-712 Smart
Name
Terminal type
A
Display
–
B
Setup button
–
C
Down button
–
D
Up button
–
E
Select button
–
F
RJ12 connector
RJ2 terminal
G
Buzzer
–
H
Programmable relay connector
Push connector
I
VE.Direct connector
VE.Direct terminal
J
Negative battery connection
M10 bolt
K
Positive battery connection
M10 ring terminal
L
Auxilary connection
Push connector
M
Negative load connection
M10 bolt
3.5. Basic electrical connections
Connection procedure:
1. Connect the negative battery terminal to the M10 bolt on the “BATTERY
ONLY” side of the shunt. Tighten the shunt bolt with a maximum torque of 21Nm.
Note that there should be no other connections on this side of the shunt or on
the negative battery terminal. Any loads or chargers connected here will be
excluded from the battery state of charge calculation.
2. Connect the negative of the electrical system to the M10 bolt on the “LOAD
AND CHARGER” side of the shunt. Tighten the shunt bolt with a maximum torque
of 21Nm. Make sure that the negative of all DC loads, inverters, battery
chargers, solar chargers and other charge sources are connected “after” the
shunt.
3. Connect the ferrule pin of the red cable with the fuse to the shunt by
pushing the pin into to the “+B1” terminal.
4. Connect the M10 eye terminal of the red cable with the fuse to the
positive terminal of the battery.
5. Connect the shunt to the head unit using the RJ12 cable. Plug one side of
the RJ12 cable into the shunt RJ12 terminal and the other side of the cable
into the RJ12 terminal on the rear of the head unit.
The battery monitor is now powered up. The display is active, and Bluetooth is
active.
In order to be fully functional, the battery monitor needs to be configured;
see the Configuration [12] chapter.
In case the battery monitor is going to be used to monitor a second battery,
battery bank midpoint or battery temperature, see one of the next 3 paragraphs
on how to do this and then go to the Configuration [12] chapter.
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Installation
Manual – BMV-712 Smart
Loads &
Chargers
Battery bank
Basic battery monitor installation.
3.6. Auxiliary electrical connections
In addition to the comprehensive monitoring of the main battery bank, a second
parameter can be monitored. This can be one of the following: · The voltage of
a second battery, like a starter battery. · The midpoint deviation of the
battery bank. · Battery temperature. This chapter describes how to wire the
+B2 terminal for the three above options.
3.6.1. Auxiliary connection for monitoring the voltage of a second battery
For use to monitor the voltage of a second battery, such as a starter or
auxiliary battery. Connection procedure: 1. Verify that the negative pole of
the second battery is connected to the LOAD AND CHARGER side of the shunt. 2.
Connect the ferrule pin of the second red cable with fuse to the shunt by
pushing the pin into to the +B2 terminal. 3. Connect the M10 lug of the second
red cable with fuse to the positive terminal of the second battery.
Loads &
Chargers
Battery monitor with auxiliary second battery monitoring.
3.6.2. Auxiliary connection midpoint battery bank monitoring
For use with a battery bank that consists of multiple batteries that are wired
in series or series/parallel to create a 24V or 48V battery bank. Connection
procedure:
Page 8
Installation
Manual – BMV-712 Smart
1. Connect the ferrule pin of the second red cable with fuse to the shunt by
pushing the pin into to the +B2 terminal. 2. Connect the M10 lug of the second
red cable with fuse to the positive terminal of the midpoint. For more
information on midpoint monitoring and for additional diagrams on midpoint
battery bank wiring see the Midpoint voltage monitoring [46] chapter.
Loads &
Chargers
Battery monitor with auxiliary midpoint monitoring.
3.6.3. Auxiliary connection for temperature monitoring
For use to monitor the temperature of a battery via the (not included)
Temperature sensor for BMV-712 Smart and BMV-702 . This temperature sensor
needs to be purchased separately. Be aware that this is a different
temperature sensor than the temperature sensors that are included with Victron
inverter/chargers and some battery chargers.
Temperature sensor for the battery monitor Connection procedure: · Connect the
ferrule pin of the black temperature sensor wire by pushing the ferule pin
into the +B2 terminal. · Connect the ferrule pin of the red wire cable by
pushing the ferule pin into to the +B1 terminal. · Connect the M10 cable lug
of the temperature sensor to the positive battery terminal.
Loads &
Chargers
Battery monitor with auxiliary temperature sensing.
Note that if the temperature sensor is used, the two red cables with fuse that
came with the battery monitor are not needed. The temperature sensor will
replace these cables.
3.7. Programmable relay
The battery monitor is equipped with a programable relay. This relay can be
used as an alarm relay, to start a generator or for other applications. For
more information on the various relay modes and how to configure the relay,
see chapter Relay settings [31].
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Installation
Manual – BMV-712 Smart
A usage example of the relay is to start a generator when the battery state of
charge has dropped too low, and then to stop the generator when the batteries
have been recharged. By default, the relay is set to energise when the battery
state of charge falls below 50% and to de-energise when the battery state of
charge has risen to 90%. However, the relay can be configured to also trigger
on other conditions, like battery voltage. The relay has 3 contacts: COM
(common), NO (normally open), and NC (normally closed) and are located on the
back of the head unit. When the relay contact is open, the coil is de-
energised; there is no contact between COM and NO. When the relay is
energised, the relay closes, and contact between COM and NO is made. The relay
function can be inverted: de-energised becomes energised and vice versa. See
setting Invert relay [32].
The internal wiring diagram of the battery monitor with the relay in a de-
energised state connected to an external alarm or generator start circuit.
3.8. Use of alternative shunts
The battery monitor is supplied with a 500A, 50mV shunt. This shunt is
suitable for most applications. However, a larger shunt will be required if
system currents above 500A are expected.
The battery monitor can be configured to work with a wide range of different
shunts. Shunts of up to 9999A and up to 75mV can be used. For a selection of
larger shunts, i.e. 1000A, 2000A or 6000A, see our shunt product page.
When using a shunt other than the one supplied with the battery monitor,
please proceed as follows:
1. Unscrew the circuit board from the shunt.
2. Mount the circuit board on the new shunt, and ensure that there is good
electrical contact between the circuit board and the shunt.
3. Connect the new shunt to the electrical system and battery monitor head
unit as shown in chapter Basic electrical connections [7]. Pay special
attention to the orientation of the shunt circuit board in relation to the
battery and load connections.
4. Follow the setup wizard; see the Setup wizard [12] chapter.
5. After completing the setup wizard, set the proper shunt current and shunt
voltage according to the Shunt current [40] and the Shunt voltage [40]
settings.
6. If the battery monitor reads a non-zero current, even when there is no
load, and the battery is not being charged, calibrate the zero current reading
using the Zero current calibration [31] setting.
3.9. GX device connection
If the system contains a GX device such as a Cerbo GX, the battery monitor can
be connected to the GX device using a VE.Direct cable or a VE.Direct to USB
interface.
Once connected, the GX device can be used to read out all monitored battery
parameters. For more information see chapter Connecting to a GX device and the
VRM portal [25].
Loads &
Chargers
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The battery monitor is connected to a Cerbo GX and a GX Touch screen.
3.10. Wiring for use as DC meter
When using the battery monitor as a DC meter, wire it to the device or circuit
that needs to be monitored. Note that the battery monitor also needs to be
configured as a DC monitor using the VictronConnect app before it will operate
as a DC monitor. See the Configure for use as DC meter [17] chapter.
It is also possible to have a main battery monitor in the system together with
a separate battery monitor that has been set up as a DC meter to monitor a
specific device or circuit.
Wiring example of a system containing a main battery monitor, together with a
battery monitor that has been set up as a DC meter and is monitoring a
specific device or circuit. One battery monitor is used as a DC meter (B) and
the other battery monitor
is used as a battery monitor (D).
Description
A
Specific DC device or DC circuit
B
Battery monitor used as DC meter
C
The rest of the DC circuit
D
Battery monitor used as battery monitor
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4. Configuration
Once the electrical connections have been made, and the battery monitor has
been powered up, it needs to be configured to be suitable for the system it is
used in.
This can be done with the buttons on the battery monitor head unit or even
easier via the VictronConnect app.
This chapter describes how to configure the battery monitor by making the
basic settings. See the All features and settings [28] chapter for all
settings and features.
4.1. Setup wizard
The battery monitor will automatically start the setup wizard on the first
power-up or after a factory reset. The setup wizard must be completed before
any other settings are made.
Alternatively, use the VictronConnect app to configure the battery monitor.
This will override the setup wizard.
1. The display shows the scrolling text “battery capacity”:
.
2. Press any button to enter the setup wizard. The scrolling text will stop,
and the factory default battery capacity value (200 Ah) will be shown with the
first digit blinking.
3. Use the + and buttons to set the first digit of the battery capacity
value. Preferably use the 20-hour (C20) battery capacity rating. For more
information on battery capacity, see the Battery capacity and Peukert exponent
[44] chapter.
4. Press SELECT to set the next digit in the same manner. Repeat this step
until the required battery capacity is displayed.
5. Press SELECT to store the value. A short beep confirms this. Should a
correction need to be made, press SELECT again and repeat the previous steps.
6. Press SETUP, + or to proceed to the auxiliary input setting.
7. The display will show the scrolling text
(auxiliary input).
8. Press SELECT to stop scrolling, and the LCD will show:
(start).
9. Use the + or buttons to select the required function of the auxiliary input:
voltage. sensor.
(mid) for monitoring the midpoint voltage of a battery bank.
(start) for monitoring the starter battery (temp) for using the optional temperature
10. Press SELECT to store the value. A short beep confirms this. Should a correction need to be made, press SELECT again and repeat the previous step.
11. Press the SETUP, + or button to end the setup wizard and switch to the normal operating mode.
Immediately after the completion of the setup wizard, the battery monitor will
automatically detect the nominal voltage of the battery system. For details
and limitations of automatic voltage detection, see the next chapter Automatic
voltage detection [12].
The battery monitor is now ready for use. It is now set up for an average
system with GEL, AGM or flooded lead-acid batteries. Further battery monitor
configurations are required if your system contains a battery with different
chemistry, like lithium, or if other specific system settings are needed. See
the All features and settings [28] chapter.
If the setup wizard is not showing, i.e. there is no scrolling text, it can be
re-activated by performing a battery monitor reset. To do this: simultaneously
press the SETUP and the SELECT button for 3 seconds. This resets the battery
monitor to its factory settings.
Note that factory settings can only be restored if the Lock setup [39] setting
has been set to OFF.
4.2. Automatic voltage detection
The battery monitor will automatically adjust itself to the nominal voltage of
the battery bank. This happens immediately after the completion of the setup
wizard. The below table shows how the nominal voltage is determined and to
what nominal battery voltage the battery monitor is automatically set. See the
Set charged voltage value [15] chapter for more information.
Measured voltage < 18V
18 – 36V
Assumed nominal voltage 12V 24V
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Measured voltage > 36V
Assumed nominal voltage 48V
Note that the battery monitor is unable to detect a 32V nominal battery voltage. If the battery monitor is used with a 32V battery bank, the charged voltage must be set manually using the Charged voltage [29] setting.
4.3. How to change settings
4.3.1. Settings via the head unit
Use the display buttons to enter and navigate through the settings menu. Each
setting has a number and a name. For example: “01 – Battery capacity”. The
full list of all battery settings and their corresponding number can be found
in the All features and settings [28] chapter.
It is also possible (and easier) to make the battery monitor settings via the
VictronConnect app. See the The VictronConnect app [14] chapter on how to do
this.
Display
Setup button
Select button
+ (up) and – (down) buttons
BMV head unit display and buttons.
To access the settings menu and change settings:
1
Start in the main menu.
2
Press SETUP for two seconds to enter the settings menu.
3
The first setting item 01-Battery capacity will be shown.
4
Use the + and buttons to go to the desired setting item.
5
Press SELECT to access the setting item.
6
Use SELECT and the + and buttons to customize the setting.
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7
Press SETUP to return to the setting menu.
8
Go to the next setting using the + or – buttons.
9
After all settings have been made, press SETUP to return from the settings menu to normal mode.
4.3.2. The VictronConnect app
The VictronConnect app can be used to change all settings and to update the
firmware. Ways to connect to the battery monitor: · Locally via built-in
Bluetooth.
· Locally via USB using the VE.Direct to USB interface connected to the
VE.Direct port.
· Remotely via a GX device, using VictronConnect “Remote” feature. For more
information, see the VictronConnect-Remote chapter in the VictronConnect app
manual.
How to connect with the VictronConnect app to the battery monitor: · Open the
VictronConnect app.
· Ensure that the battery monitor is powered.
· Look for the battery monitor to appear in the device list in the “Local” or
the “VRM” tab.
· Click on the battery monitor.
· In case of a connection via Bluetooth; enter the default PIN code: 000000.
After entering the default PIN code, the VictronConnect app will ask you to
change the PIN code. This is to prevent unauthorized connections in the
future. It is recommended that you change the PIN code on the first
installation. This can be done in the product info tab; see paragraph Changing
PIN code [42].
To view and/or change battery monitor settings, navigate to the settings page
by clicking on the cog icon at the top right of the home screen.
The battery monitor monitoring and setting screens in the VictronConnect app.
Note that this manual only covers the items that are specific to the battery
monitor. For more general information about the VictronConnect app, like how
to use it and where to download it, or how to connect, see the VictronConnect
app product page and manual.
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4.4. Update firmware
On a new install, it is recommended to update the firmware of the battery
monitor. If there is a newer firmware version available, the VictronConnect
app will notify you of this as soon as a connection with the battery monitor
is made.
Note that the firmware can only be updated via the VictronConnect app. The app
needs to be up to date to be able to access the latest firmware.
To check if the firmware is up to date or to manually update firmware, connect
to the battery monitor using the VictronConnect app and follow the below
steps: · Navigate to the product settings by clicking the “cog” symbol in the
top right-hand corner of the product status screen. · Click on the “3 dots”
symbol in the top right-hand corner of the settings screen. · Select “Product
info” from the pop-up menu. · The firmware version will be displayed. It is
mentioned if this is the latest firmware version (or not). If a newer firmware
version
is available, an “UPDATE” button will be displayed. · To update the firmware,
press the “UPDATE” button.
4.5. Make essential settings
The default settings of the battery monitor are tailored for lead acid
batteries, like AGM, GEL, OPzV or OPzS batteries. Most settings can stay at
their factory default. But there are a few settings that need to be changed.
These are: · Battery capacity. · Charged voltage. · The functionality of the
auxiliary input (if used). · State of charge or start synchronised.
If lithium batteries (or batteries with a different chemistry) are used, some
additional settings will have to be changed. First, make the essential
settings as described in this paragraph and then refer to the next paragraph
for the special lithium settings.
For more information about these and any of the other settings, see chapter
All features and settings [28].
4.5.1. Set the battery capacity value
In the VictronConnect app, see: Settings > Battery.
Via the head unit, see: Setup menu > Setting 01 – Battery capacity.
The battery monitor is by default set to 200Ah. Change this value to match
your battery capacity. For lead-acid batteries, we recommend entering the
20-hour (C20) rate.
4.5.2. Set charged voltage value
In the VictronConnect app, see: Settings > Battery > Charged voltage. Via the
head unit, see: Setup menu > Setting 02 – Charged voltage. Although the
battery monitor automatically detects the voltage, it is good practice to
check if this setting is correctly set.
Nominal battery voltage 12V 24V 36V 48V
Recommended charged voltage setting 13.2V 26.4V 39.6V 52.8V
For more information, also see the Charged voltage [29] chapter.
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4.5.3. Set state of charge
In the VictronConnect app, see: Settings > Battery > Battery start
synchronized. Via the head unit, see: Setup menu > Setting 70 – Start
synchronised. When set to ON, the battery monitor will consider itself
synchronized when powered up, resulting in a state of charge of 100%. If set
to OFF, the battery monitor will consider itself un-synchronized when powered
up, resulting in a state of charge that is unknown until the first actual
synchronization. For VictronConnect only: The initial state of charge value
can also be manually set, by default, this is 100%, and can be set to a
different value if so desired. See: Settings > Battery > State-of-charge.
4.5.4. Set the auxiliary input function
In the VictronConnect app, see: Settings > Misc > Aux input. Via the display,
see: Settings menu > Setting 69 – Aux input. This setting sets the function of
the auxiliary input, being: · Starter battery – Voltage monitoring of a second
battery.
· Midpoint – Measuring the midpoint of a battery bank.
· Temperature – Measuring battery temperature via an optional temperature
sensor.
· None – The auxiliary input is not used.
4.6. Make Lithium settings (if needed)
LiFePO4 (Lithium Iron Phosphate or LFP) is the most used Li-ion battery
chemistry. The factory defaults are in general also applicable to LFP
batteries with exception of these settings: · Tail current.
· Peukert exponent.
· Charge efficiency.
· Discharge floor.
Tail current In VictronConnect see: Settings > Battery > Tail current. Via the
head unit, see: Setup menu > Setting 03 – Tail current. Some lithium battery
chargers stop charging when the current drops below a set threshold. The tail
current must be set higher in this case. Peukert exponent In VictronConnect
see: Settings > Battery > Peukert exponent. Via the head unit, see: Setup menu
Setting 05 – Peukert exponent. When subjected to high discharge rates, lithium batteries perform much better than lead-acid batteries. Set the Peukert exponent at 1.05, unless the battery supplier advises otherwise. Charge efficiency In VictronConnect see: Settings > Battery > Charge efficiency factor. Via the head unit, see: Setup menu > Setting 06 – Charge efficiency factor. The charge efficiency of lithium batteries is much higher than that of lead-acid batteries. We recommend setting the charge efficiency at 99%. Discharge floor In VictronConnect see: Setting > Battery > Discharge floor Via the head unit, see: Setup menu > Setting 16 – SoC relay. This setting is used in “the time to go” calculation and is set at 50% by default for lead-acid batteries. However, lithium batteries usually can be discharged significantly deeper than 50%. The discharge floor can be set to a value between 10 and 20%, unless the battery supplier advises otherwise.
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Important warning Lithium batteries are expensive and can be irreparably
damaged due to very deep discharge or overcharge. Damage due to deep discharge
can occur if small loads slowly discharge the battery when the system is not
in use. Some examples of these loads are alarm systems, standby currents of DC
loads and back current drain of battery chargers or charge regulators. A
residual discharge current is especially dangerous if the system has been
discharged all the way until a low cell voltage shutdown has occurred. At this
moment the state of charge can be as low as 1%. The lithium battery will get
damaged if any remaining current is drawn from the battery. This damage can be
irreversible. A residual current of 1mA for example can damage a 100Ah battery
if the battery has been left in a discharged state for more than 40 days (1mA
x 24h x 40 days = 0.96Ah). The battery monitor draws <12mA from the battery.
The positive supply must therefore be interrupted if a system with Li-ion
batteries is left unattended during a period long enough for the battery
monitor power consumption to completely discharge the battery. In case of any
doubt about the possible residual current draw, isolate the battery by opening
the battery switch, by pulling the battery fuse(s) or by disconnecting the
battery positive when the system is not in use.
4.7. Configure for use as DC meter
In the VictronConnect battery monitor settings, go to the “Misc” settings and
select “DC energy meter” from the Monitor mode drop-down menu. Once selected,
you can choose what application the DC energy meter is used in. Alternatively,
navigate to setting 72 on the head unit. For additional information also see
the Monitor Mode [41] chapter.
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5. Operation
Manual – BMV-712 Smart
5.1. How does the battery monitor work?
The main function of the battery monitor is to follow and indicate the state
of charge of a battery, to be able to know how much charge the battery
contains and to prevent an unexpected total discharge.
The battery monitor continuously measures the current flow in and out of the
battery. Integration of this current over time, if it was a fixed current,
boils down to multiplying current and time and gives the net amount of Ah
added or removed.
For example, a discharge current of 10A for 2 hours will take 10 x 2 = 20Ah
from the battery.
To complicate matters, the effective capacity of a battery depends on the rate
of discharge, the Peukert efficiency, and, to a lesser extent, the
temperature. And to make things even more complicated: when charging a battery
more energy (Ah) has to be `pumped’ into the battery than can be retrieved
during the next discharge. In other words: the charge efficiency is less than
100%. The battery monitor takes all these factors into consideration when
calculating the state of charge.
5.2. Readout overview
The head unit display or the VictronConnect app battery monitor status screen,
displays an overview of the most important parameters. These are:
· State of charge
· Battery voltage
· Battery current
· Power
· Aux input reading (starter battery, midpoint or temperature)
State of charge
This is the actual state of charge of the battery in a percentage and is
compensated for both the Peukert efficiency and charge efficiency. The state
of charge is the best way to monitor the battery.
A fully charged battery will be indicated by a value of 100.0%. A fully
discharged battery will be indicated by a value of 0.0%.
Please note that if the state of charge indicates three dashes: “—” this means
that the battery monitor is in an unsynchronised state. This mainly occurs
when the battery monitor has just been installed or after the battery monitor
has been left unpowered and is powered up again. For more information, see the
Synchronising the battery monitor [23] chapter.
Voltage
This is the terminal voltage of the battery.
Current
This is the actual current flowing in or out of the battery. A negative
current indicates that current is taken from the battery. This is the current
needed for DC loads. A positive current means that current is going into the
battery. This is current coming from charge sources. Keep in mind that the
battery monitor will always indicate the total battery current, being the
current traveling into the battery minus the current traveling out of the
battery.
Power
The power drawn from or received by the battery.
Consumed Ah
The battery monitor keeps track of the Amp-hours removed from the battery
compensated for the efficiency.
Example: If a current of 12A is drawn from a fully charged battery for a
period of 3 hours, the readout will show -36.0Ah (-12 x 3 = -36).
Please note that if the “Consumed Ah” reading indicates three dashes: “—” this
means that the battery monitor is in an unsynchronised state. This mainly
occurs when the battery monitor has just been installed or after the battery
monitor has been left unpowered and is powered up again. For more information,
see the Synchronising the battery monitor [23] chapter.
Time remaining
The battery monitor estimates how long the battery can support the present
load. This is the “time-to-go” readout and is the actual time left until the
battery is discharged to the set “discharge floor”. The discharge floor is by
default set at 50%. For the discharge floor setting see the Discharge floor
[29] chapter. If the load is fluctuating heavily, it is best not to rely on
this reading too much,
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as it is a momentary readout and should be used as a guideline only. We
recommend the use of the state of charge readout for accurate battery
monitoring.
If the “Time remaining” indicates three dashes: “—” this means that the
battery monitor is in an unsynchronised state. This occurs when the battery
monitor has just been installed or after it has been left unpowered and is
powered up again. For more information, see see the Synchronising the battery
monitor [23] chapter.
Input
This is the state of the auxiliary input. Depending on how the battery monitor
has been set up, you will see one of these options:
· Starter battery voltage: This shows the voltage of a second battery.
· Battery temperature: This shows the battery temperature of the main battery
when the optional temperature sensor is used.
· Midpoint voltage deviation: This shows the deviation in a percentage of the
main voltage of the battery bank top section compared to the voltage of the
bottom section. For more information on this feature see the Midpoint voltage
monitoring [46] chapter.
5.3. Using the head unit menus
Alternatively, use the VictronConnect app to access the battery monitor
settings. See the chapter The VictronConnect app [14] on how to do this.
When the battery monitor is powered up for the first time or when the factory
settings have been restored, the battery monitor will start the quick setup
wizard; see chapter: Setup wizard [12]. After that, the battery monitor will
operate in normal mode, and the battery menu can be accessed as described in
this chapter.
The battery monitor is controlled by the four buttons on the head unit. The
function of the buttons depends on which mode the battery monitor is in. This
is indicated in the below table.
If the backlight is off, press any button to restore the backlight.
Button SETUP
SELECT
SETUP and SELECT
simultaneously +
+ and simultaneously
Function when in normal mode
Press and hold for two seconds to switch to setup mode. The display will
scroll the number and description of the selected parameter.
Press to switch to the history menu. Press to stop scrolling and show the
value. Press again to switch back to normal mode.
Press and hold both SETUP and SELECT buttons simultaneously for three seconds
to restore factory settings (disabled when setting 64, lock setup, is on, see
Lock setup [39]).
Move upwards.
Move downwards. Press and hold for three seconds (until the confirmation beep)
to start or stop automatic cycling through status items. Press and hold both
buttons simultaneously for three seconds to manually synchronise the BMV.
Function when in setup mode Press SETUP any time to return to the scrolling
text, and press again to return to normal mode. When pressing SETUP while a
parameter is out of range, the display blinks five times, and the nearest
valid value is displayed. · Press to stop scrolling after entering the setup
mode with the SETUP button.
· After editing the last digit, press to end editing. The value is stored
automatically. A short beep indicates confirmation.
· If required, press again to restart editing.
n/a
When not editing, press to move up to the previous parameter. When editing,
this button will increment the value of the selected digit. When not editing,
press to move down to the next parameter. When editing, this button will
decrement the value of the selected digit.
n/a
5.4. Trends
The VictronConnect app provides battery monitor data logging. Providing that
the firmware battery monitor is up to date, the battery monitor will store up
to 45 days of past data and two of the following parameters can be viewed
alongside:
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· Voltage (V). · Current (A). · Power (W). · Consumed Amp Hours (Ah). · State of charge (%). · Temperature (°C).
Manual – BMV-712 Smart
VictronConnect app battery monitor trends.
5.5. History
The battery monitor stores historic events. These can be used at a later date
to evaluate usage patterns and battery health. The history data is stored in a
non-volatile memory and will not be lost when the power supply to the battery
monitor has been interrupted or when the battery monitor has been reset to its
defaults.
5.5.1. Accessing historical data via the VictronConnect app
The battery monitor’s historical data can be accessed in the “History” tab in
the VictronConnect app.
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The VictronConnect app battery monitor history screen.
5.5.2. Accessing historical data via the head unit
To view the battery monitor history menu press SELECT when in normal mode: ·
Press + or to browse the various parameters.
· Press + or to browse the various values.
· Press SELECT again to stop scrolling and show the value.
· Press SELECT again to leave the historical menu and to go back to the normal
operation mode.
The below table gives an overview of the history parameters and how they are
displayed in the menu. For the meaning of each parameter see the next chapter.
Display
Discription
A
Deepest discharge
B
Last discharge
C
Average discharge
D
Cycles
E
Discharges
F
Cumulative Ah
G
Lowest voltage
H
Highest voltage
I
Days since last full charge
J
Synchronisations
L
Low voltage alarms
M
High voltage alarms
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Display
Discription
P
Lowest AUX voltage
Q
Highest AUX voltage
R
Discharged energy
S
Charged energy
5.5.3. History data
Discharge information in Ah · Deepest discharge: The battery monitor remembers
the deepest discharge and each time the battery is discharged deeper
the old value will be overwritten. · Last discharge: The battery monitor keeps
track of the discharge during the current cycle and displays the largest value
recorded for Ah consumed since the last synchronisation. · Average discharge:
The cumulative Ah drawn divided by the total number of cycles. · Cumulative Ah
drawn: The cumulative number of Amp hours drawn from the battery over the
lifetime of the battery monitor. Energy in kWh · Discharged energy: This is
the total amount of energy drawn from the battery in kWh. · Charged energy:
The total amount of energy absorbed by the battery in kWh. Charge · Total
charge cycles: The number of charge cycles over the lifetime of the battery
monitor. A charge cycle is counted every
time the state of charge drops below 65% and then rises above 90%. · Time
since last full charge: The number of days since the last full charge. ·
Synchronisations: The number of automatic synchronisations. A synchronisation
is counted every time the state of charge
drops below 90% before a synchronisation occurs. · Number of full discharges:
The number of full discharges. A full discharge is counted when the state of
charge reaches 0%. Battery voltage · Min battery voltage: The lowest battery
voltage. · Max battery voltage: The highest battery voltage. · Min starter
voltage: The lowest auxiliary battery voltage (if applicable). · Max starter
voltage: The highest auxiliary battery voltage (if applicable). Voltage alarms
· Low voltage alarms: The number of low voltage alarms. · High voltage alarms:
The number of high voltage alarms.
5.6. Alarms
The battery monitor can raise an alarm in the following situations: · Low
battery state of charge (SOC). · Low battery voltage. · High battery voltage.
· Low and high starter battery voltage (if the AUX input has been set to
“Starter battery”). · Midpoint voltage (if the AUX input has been set to
“Midpoint”). · High and Low battery temperature (if the AUX input has been set
to “Temperature”).
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The alarm will activate when the value reaches a set threshold and will
deactivate when the value clears this threshold. The thresholds are
configurable. For more information, see the Alarm settings [34] chapter. The
alarm will be displayed on the head unit, a buzzer will sound, the display
backlight will flash, and the alarm icon will be visible on the display. An
alarm is acknowledged when a button is pressed. However, the alarm icon is
displayed as long as the alarm condition remains. The programmable relay can
be triggered depending on the configuration of the alarm settings. The alarm
is also a software alarm. When connecting with the VictronConnect app, while
an alarm is active, the alarm will show in the app. Alternatively, when the
battery monitor is connected to a GX device, the alarm will show on the GX
device display or the VRM portal. In the case of the VictronConnect app, an
alarm is acknowledged when a button is pressed. And in the case of a GX
device, an alarm is acknowledged when viewed in notifications. The alarm icon
is displayed as long as the alarm condition remains.
Left: alarm displayed on the VictronConnect app. Right: alarm displayed on a
GX device.
5.7. Synchronising the battery monitor
For a reliable readout, the state of charge, as displayed by the battery
monitor, must self-synchronise regularly with the true state of charge of the
battery. This is to prevent drift of the “State of charge” value over time. A
synchronisation will reset the state of charge of the battery to 100%.
5.7.1. Automatic synchronisation
Synchronisation is an automatic process and will occur when the battery has
been fully charged. The battery monitor will look at a few parameters to
ascertain that the battery has been fully charged. It will consider the
battery to be fully charged when the voltage has reached a certain value and
the current has dropped below a certain value for a certain amount of time.
These parameters are called: · Charged voltage – the float voltage of the
battery charger.
· Tail current – a percentage of the battery capacity.
· Charged detection time – the time in minutes.
As soon as these 3 parameters have been met, the battery monitor will set the
state of charge value to 100%, thus synchronising the state of charge.
Example: In the case of a 12V battery, the battery monitor will reset the
battery’s state of charge to 100% when all these parameters have been met: ·
The voltage exceeds 13.2V,
· the charge current is less than 4.0% of the total battery capacity (e.g. 8A
for a 200Ah battery) and,
· 3 minutes have passed while both the voltage and current conditions are met.
If the battery monitor does not perform a regular synchronisation, the state
of charge value will start to drift over time. This is due to the small
inaccuracies of the battery monitor and because of the estimation of the
Peukert exponent [44]. Once a battery has been fully charged, and the charger
has gone to the float stage, the battery is full and the battery monitor will
automatically synchronise by setting the state of charge value to 100%.
5.7.2. Manual synchronisation
The battery monitor can be synchronised manually if required. This can be done
by pressing the “Synchronise” button in the VictronConnect app. Navigate to
“settings” and then to “battery settings”. Alternatively, the battery monitor
can be synchronised when in normal operating mode by simultaneously pressing
and holding the + and buttons for 3 seconds. A manual synchronisation can be
needed in situations when the battery monitor does not synchronise
automatically. This is for example needed during the first installation or
after the voltage supply to the battery monitor has been interrupted.
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Operation
Manual – BMV-712 Smart A manual synchronisation can also be needed when the
battery has not been fully charged, or if the battery monitor has not detected
that the battery has been fully charged because the charged voltage, current
or time has been set incorrectly. In this case, review the settings and make
sure the battery regularly receives a full charge.
5.8. Operation as a DC meter
The battery monitor can be set up as a DC energy meter. It is used to measure
DC production or consumption of a specific device in a system, like for
example an alternator, wind turbine or hydro generator. Or similarly, the
consumption of a specific circuit or load in a DC system. When in DC monitor
mode, the voltage, current and power is displayed.
VictronConnect app status screen of a battery monitor running in DC monitor
mode. Note that the wiring of a DC meter differs from battery monitor wiring,
see the Wiring for use as DC meter [11] chapter on how to wire. When switching
between modes, it is recommended to reset all historical data.
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6. Interfacing
The battery monitor can be connected to other equipment, this chapter
describes how this can be done.
6.1. VictronConnect app via USB
The VictronConnect app can not only connect via Bluetooth but it can also
connect via USB. A USB connection is essential when connecting to the Windows
version of the VictronConnect app and is optional when the MacOS or Android
version is used. Please note that in case of connecting to an Android phone or
tablet a “USB on the Go” cable might be needed. To connect via USB, you will
need a VE.Direct to USB interface. Use this interface to connect the computer
to the battery monitor. for more information see the VE.Direct to USB
interface product page. For more information also see the VictronConnect app
manual.
Example of a VE.Direct to USB interface connection between the battery monitor and a computer.
Description
A
VE.Direct to USB interface.
B
Computer or laptop.
6.2. Connecting to a GX device and the VRM portal
A GX device, such as the Cerbo GX, is a Victron Energy device that provides
control and monitoring for all Victron equipment that is connected to it.
Control and monitoring of the GX device and it’s connected equipment can be
done locally or remotely via our free Victron Remote Monitoring portal, the
VRM portal.
The battery monitor can be connected to a GX device with a VE.Direct cable.
The VE.Direct cables are available in lengths ranging from 0.3 to 10 meters
and are available with straight or right-angle connectors. Alternatively, the
battery monitor can also connect to a GX device using a VE.Direct to USB
interface.
Once connected, the GX device can be used to read out all monitored battery
parameters.
Battery monitor information displayed by a GX device.
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Example of a battery monitor connecting to a GX device.
6.3. Connecting to VE.Smart networking
VE.Smart networking is a wireless network that allows a number of Victron
products to exchange information via Bluetooth. The battery monitor can share
the following information with the network: · Battery voltage. · Battery
current. · Battery temperature. Note that an optional temperature sensor is
needed see chapter Auxiliary connection for temperature
monitoring [9] for more information. A usage example is a system with VE.Smart
networking that contains a battery monitor with a temperature sensor and a
solar charger. The solar charger receives the battery voltage and temperature
information from the battery monitor and uses this information to optimise its
charge parameters. This will improve charging efficiency and will prolong
battery life. To make the battery monitor part of VE.Smart networking, you
will have to either create a network or join an existing network. The setting
can be found in the VictronConnect app. Navigate to the battery monitor page
and then to: settings > smart networking. Please see the VE.Smart networking
manual for more information.
Creating a VE.Smart network using the VictronConnect app.
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Example of a system containing a battery monitor with a temperature sensor and
a solar charger, both using the VE.Smart networking.
6.4. Custom integration
Please note that this is an advanced feature and requires programming
knowledge. The VE.Direct communications port can be used to read data and
change settings. The VE.Direct protocol is extremely simple to implement.
Transmitting data to the battery monitor is not necessary for simple
applications: the battery monitor automatically sends all readings every
second. All the details are explained in the Data communication with Victron
Energy products document.
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7. All features and settings
This chapter explains all battery monitor settings. In addition to this we
also have a video available explaining these settings and how the interact
with each other to achieve accurate battery monitoring for both lead acid and
lithium batteries.
Link to the video:
7.1. How to change settings
Settings can be changed by using the battery monitor’s head unit or by using
the VictronConnect app.
7.1.1. Accessing settings via the head unit
To access and change setting parameters use the buttons on the head unit in
the following way: · Press SETUP for two seconds to access these functions and
use the+ and buttons to browse them. · Press SELECT to access the desired
parameter. · Use SELECT and the + and buttons to customize. A short beep
confirms the setting. · Press SETUP at any time to return to the scrolling
text, and press again to return to normal mode.
7.1.2. Accessing settings via the VictronConnect app
To access and change setting parameters do the following:
· Click on the settings symbol to go to the battery settings menu.
· To navigate from the general settings menu to the product settings menu,
click on the menu symbol .
For information on how to connect with the VictronConnect app to the battery
monitor, see the The VictronConnect app [14] chapter.
7.1.3. Saving, loading and sharing settings in VictronConnect
In the settings menu you can find the following 3 symbols:
Save settings to file – This will save settings for reference or for later
use.
Load settings from file – This will load earlier saved settings.
Share settings file This allows you to share the settings file via email,
message, airdrop and so on. The available sharing options depend on the
platform used. For more information on these features, see the VictronConnect
manual.
7.2. Battery settings
The battery settings can be used to fine-tune the battery monitor. Please be
careful when you change these settings, as a change might affect the battery
monitor’s state of charge calculations.
7.2.1. Battery capacity
This parameter is used to tell the battery monitor how big the battery is.
This setting should already have been done during the initial installation.
The setting is the battery capacity in Amp-hours (Ah).
For more information on the battery capacity and the related Peukert exponent
see the Battery capacity and Peukert exponent [44] chapter.
Setting Battery capacity (setting 01)
Default 200Ah
Range 1 – 9999Ah
Step size 1Ah
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7.2.2. Charged voltage
The battery voltage must be above this voltage level to consider the battery
as fully charged. As soon as the battery monitor detects that the voltage of
the battery has reached this “charged voltage” parameter and the current has
dropped below the “tail current [29]” parameter for a certain amount of time,
the battery monitor will set the state of charge to 100%.
Setting Charged voltage (setting 02)
Default 13.2V (12V nominal) 26.4V (24V nominal) 52.8V (48V nominal)
Range 0 – 70V
Step size 0.1V
The “charged voltage” parameter should be set to 0.2V or 0.3V below the float voltage of the charger. The table below indicates the recommended settings for lead acid batteries.
Nominal battery voltage 12V 24V 36V 48V
Charged voltage setting 13.2V 26.4V 39.6V 52.8V
7.2.3. Discharge floor
The “Discharge floor” parameter is used in the “time remaining” calculation.
The battery monitor calculates the time it takes until the set “discharge
floor [29]” has been reached. It is also used to set the state of charge alarm
defaults.
For lead-acid batteries set this to 50% and for lithium set it lower.
Note that this setting only appears when accessing the battery monitor via the
VictronConnect app. In case the battery monitor is accessed via the head unit,
see the Low State of Charge (SoC) relay [32] setting instead.
Setting Discharge floor
Default setting 50%
Range 0 – 99%
Step size 1%
7.2.4. Tail current
The battery is considered as fully charged once the charge current has dropped
to less than this “Tail current” parameter. The “Tail current” parameter is
expressed as a percentage of the battery capacity.
Note that some battery chargers stop charging when the current drops below a
set threshold. In these cases, the tail current must be set higher than this
threshold.
As soon as the battery monitor detects that the voltage of the battery has
reached the set “Charged voltage [29]” parameter and the current has dropped
below this “Tail current” parameter for a certain amount of time, the battery
monitor will set the state of charge to 100%.
Setting Tail current (setting 03)
Default 4.00%
Range 0.50 – 10.00%
Step size 0.1%
7.2.5. Charged detection time
This is the time the “Charged voltage [29]” parameter and the “Tail current
[29]” parameter must be met in order to consider the battery fully charged.
Setting Charged detection time (setting 04)
Default setting 3 minutes
Range 0 – 100 minutes
Step size 1 minute
7.2.6. Peukert exponent
Set the Peukert exponent parameter according to the battery specification
sheet. If the Peukert exponent is unknown, set it at 1.25 for lead-acid
batteries and set it at 1.05 for lithium batteries. A value of 1.00 disables
the Peukert compensation. The Peukert value for lead-acid batteries can be
calculated. For more information on the Peukert calculation, the Peukert
exponent and how this relates to the battery capacity, see the Battery
capacity and Peukert exponent [44] chapter.
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Setting Peukert exponent (setting 05)
Default 1.25
Range 1.00 – 1.50
Step size 0.01
7.2.7. Charge efficiency factor
The “Charge Efficiency Factor” compensates for the capacity (Ah) losses during
charging. A setting of 100% means that there are no losses.
A charge efficiency of 95% means that 10Ah must be transferred to the battery
to get 9.5Ah actually stored in the battery. The charge efficiency of a
battery depends on battery type, age and usage. The battery monitor takes this
phenomenon into account with the charge efficiency factor.
The charge efficiency of a lead acid battery is almost 100% as long as no gas
generation takes place. Gassing means that part of the charge current is not
transformed into chemical energy, which is stored in the plates of the
battery, but is used to decompose water into oxygen and hydrogen gas (highly
explosive!). The energy stored in the plates can be retrieved during the next
discharge, whereas the energy used to decompose water is lost. Gassing can
easily be observed in flooded batteries. Please note that the `oxygen only’
end of the charge phase of sealed (VRLA) gel and AGM batteries also results in
a reduced charge efficiency.
Setting Charge efficiency factor (setting 06)
Default setting 95%
Range 50 – 100%
Step size 1%
7.2.8. Current threshold
When the current measured falls below the “Current threshold” parameter it
will be considered zero. The “Current threshold” is used to cancel out very
small currents that can negatively affect the long-term state of charge
readout in noisy environments. For example, if the actual long-term current is
0.0A and, due to injected noise or small offsets, the battery monitor measures
0.05A the battery monitor might, in the long term, incorrectly indicate that
the battery is empty or will need to be recharged. When the current threshold
in this example is set to 0.1A, the battery monitor calculates with 0.0A so
that errors are eliminated.
A value of 0.0A disables this function.
Setting Current threshold (setting 07)
Default 0.10A
Range 0.00 – 2.00A
Step size 0.01A
7.2.9. Time-to-go averaging period
The time-to-go averaging period specifies the time window (in minutes) that
the moving averaging filter works. A value of 0 (zero) disables the filter and
gives an instantaneous (real-time) readout. However, the displayed “Time
remaining” value may fluctuate heavily. Selecting the longest time, 12
minutes, will ensure that only long-term load fluctuations are included in the
“Time remaining” calculations.
Setting Time-to-go averaging period (setting 08)
Default 3 minutes
Range 0 – 12 minutes
Step size 1 minute
7.2.10. Battery starts synchronised
Note that if the battery monitor settings are accessed via the head unit, this
setting will be part of the miscellaneous setting, and if accessed via
VictronConnect it will be part of the battery settings.
The battery state of charge will become 100% after the battery monitor is
powered up. When set to ON, the battery monitor will consider itself
synchronised when powered up, resulting in a state of charge of 100%. If set
to OFF, the battery monitor will consider it unsynchronised when powered up,
resulting in a state of charge that is unknown until the first actual
synchronisation.
Please be aware that situations can occur where special consideration is
needed when setting this feature to ON. One of these situations occurs in
systems where the battery is often disconnected from the battery monitor, for
example on a boat. If you leave the boat and disconnect the DC system via the
main DC breaker and at that moment the batteries were, for example, 75%
charged. On return to the boat, the DC system is reconnected and the battery
monitor will now indicate 100%. This will give a false impression that the
batteries are full, while in reality they are partially discharged.
There are two ways of solving this, one is to not disconnect the battery
monitor when the batteries are partially discharged or alternatively turn the
“Battery starts synchronised” feature off. Now when the battery monitor is
reconnected the state of charge will display “—” and will not show 100% until
the batteries have been fully charged. Please note that leaving a lead acid
battery in a partially discharged state for a length of time will cause
battery damage.
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Setting Start synchronized (setting 70)
Default ON
Modes ON/OFF
7.2.11. State of charge
With this setting, you can manually set the state of charge value. This
setting is only active after the battery monitor has, at least once, been
synchronised. Either automatically or manually.
This setting is only available when accessing the battery monitor via the
VictronConnect app.
Setting State of charge
Default — %
Range 0.0 – 100%
Step size 0.1%
7.2.12. Synchronise SoC to 100%
Setting 10
This option can be used to manually synchronise the battery monitor.
When navigating to this setting on the head unit , press the SELECT button to
synchronize the battery monitor to 100%.
In the VictronConnect app press the “Synchronise” button to synchronise the
battery monitor to 100%.
See the Manual synchronisation [23] paragraph for more information on this
setting.
7.2.13. Zero current calibration
Setting 09
This option can be used to calibrate the zero reading if the battery monitor
reads a non-zero current even when there is no load and the battery is not
being charged.
A zero current calibration is (almost) never needed. Only perform this
procedure in case the battery monitor shows a current while you are absolutely
sure that there is no actual current flowing. The only way to be sure is to
physically disconnect all wires and cables connected to the LOAD AND CHARGER
side of the shunt. Do this by unscrewing the shunt bolt and removing all
cables and wires from that side of the shunt. The alternative, switching loads
or chargers off, is NOT accurate enough as this does not eliminate small
standby currents.
Ensure that there really is no current flowing into or out of the battery
(disconnect the cable between the load and the shunt), then press SELECT in
the head unit menu or press CALIBRATE in the VictronConnect app.
Performing a zero current calibration.
7.3. Relay settings
The battery monitor is equipped with a programmable relay. These settings are
used to program the function of the relay. The relay settings are disabled by
default (except the State of Charge (SoC) relay setting). To enable, a relay
setting do the following: · In the VictronConnect app, enable the relay
setting by sliding the slider button to the right. · Via the head unit, enable
the relay setting by changing the set and clear value to any value above zero.
7.3.1. Relay mode
This setting has the following relay modes, namely:
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Setting
Relay mode (setting 11)
Default mode DFLT
Modes DFLT Default mode.
CHRG Charger mode.
REM Remote mode.
Description
The relay settings 16 up to 31 can be used to control the relay.
The relay will close when the state of charge falls below setting 16
(discharge floor) or when the battery voltage falls below setting 18 (low
voltage relay). The relay will be open when the state of charge is higher than
setting 17 (clear state of charge relay) and the battery voltage is higher
than setting 19 (clear low voltage relay).
An application example is to start and stop control of a generator, together
with settings 14 and 15.
The relay can be controlled via the VE.Direct interface. Relay settings 12 and
14 up to 31 are ignored as the relay is under the full control of the device
connected via the VE.Direct interface.
7.3.2. Invert relay
This function enables selection between a normally de-energised (contact open)
or a normally energised (contact closed) relay.
When inverted, the open and closed conditions as described in all the relay
settings are inverted (with the exception of the Relay state [32]).
Note that the “normally energised” setting will slightly increase the power
consumption of the battery monitor.
Setting Invert relay (setting 12)
Default mode OFF
Modes OFF ON
Range Normally de-energised
Normally energised
7.3.3. Relay state
This is a read-only parameter and it displays whether the relay is open or
closed (de-energised or energised).
Setting Relay state (setting 13)
Value OPEN CLSD
Description The relay is open (de-energised) The relay is closed (energised)
7.3.4. Relay minimum closed time
Sets the minimum time the “closed” condition will remain present after the
relay has been energised. Note that this changes to “open” and de-energised if
the relay function has been inverted (Invert relay [32] setting). An
application example is to set a minimum generator run time when the relay is
set to “charger” mode (Relay mode [31] setting).
Setting Relay minimum closed time (setting 14)
Default 0 minutes
Range 0 – 8 hours
Step size 1 minute
7.3.5. Relay off delay
Sets the amount of time the “de-energise relay” condition must be present
before the relay opens.
An application example is to keep a generator running for a while to charge
the battery better when the relay is set to “charger” mode (Relay mode [31]
setting).
Setting Relay off delay (setting 15)
Default 0 minutes
Range 0 – 500 minutes
Step size 1 minute
7.3.6. Low State of Charge (SoC) relay
When the state of charge percentage has fallen below the “set relay” value,
the relay will close.
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When the state of charge percentage has risen above the “clear relay” value,
the relay will open (after a delay, depending on the Relay minimum closed time
[32] and/or the Relay off delay [32] settings).
The “clear relay” value needs to be greater than the “set relay” value.
Setting Set relay value (setting 16) Clear relay value (setting 17)
Default 50% 90%
Range 0 – 99% 0 – 99%
Step size 1% 1%
When the “set relay” and “clear relay” values are equal, the state of charge condition will be unable to drive the relay.
Note that this setting is also known as the discharge floor. The time-to-go reading displayed by the battery monitor relates to this setting. The time to go is the time left until this setting (the discharge floor) has been reached.
7.3.7. Low voltage relay
When the battery voltage falls below the “set relay” value for more than 10
seconds the relay will close.
When the battery voltage rises above the “clear relay” value, the relay will
open (after a delay, depending on the Relay minimum closed time [32] and/or
the Relay off delay [32] settings).
The “clear relay” value needs to be greater than the “set relay” value.
Setting Set relay value (setting 18) Clear relay value (setting 19)
Default 0V 0V
Range 0 – 95V 0 – 95V
Step size 0.1V 0.1V
7.3.8. High voltage relay
When the battery voltage rises above the “set relay” value for more than 10
seconds the relay will close.
When the battery voltage falls below the “clear relay” value, the relay will
open (after a delay, depending on the Relay minimum closed time [32] and/or
the Relay off delay [32] settings).
The “clear relay” value needs to be greater than the “set relay” value.
Setting Set relay value (setting 20) Clear relay value (setting 21)
Default 0V 0V
Range 0 – 95V 0 – 95V
Step size 0.1V 0.1V
7.3.9. Low starter voltage relay
This setting is available if the aux input has been set to “Starter battery”,
see the Aux input [40] setting.
When the auxiliary (e.g. starter battery) voltage falls below “set relay”
value for more than 10 seconds, the relay will be closed.
When the auxiliary voltage rises above the “clear relay” value, the relay will
open (after a delay, depending on the Relay minimum closed time [32] and/or
the Relay off delay [32] settings).
The “clear relay” value needs to be greater than the “set relay” value.
Setting Set relay value (setting 20) Clear relay value (setting 21)
Default 0V 0V
Range 0 – 95V 0 – 95V
Step size 0.1V 0.1V
7.3.10. High starter voltage relay
This setting is available if the aux input has been set to “Starter battery”,
see the Aux input [40] setting.
When the auxiliary (e.g. starter battery) voltage rises above the “set relay”
value for more than 10 seconds, the relay will be closed.
When the auxiliary voltage falls below the “clear relay” value, the relay will
open (after a delay, depending on the Relay minimum closed time [32] and/or
the Relay off delay [32] settings).
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The “clear relay” value needs to be greater than the “set relay” value.
Setting Set relay value (setting 24) Clear relay value (setting 25)
Default 0V 0V
Range 0 – 95V 0 – 95V
Step size 0.1V 0.1V
7.3.11. Low temperature relay
This setting is available if the aux input has been set to “Temperature”, see
the Aux input [40] setting.
Use the Temperature unit setting [41] to choose between °C or °F temperature
units.
When the battery temperature drops below the “set relay” value for more than
10 seconds the relay will close.
When the battery temperature rises above the “clear relay” value, the relay
will open (after a delay, depending on the Relay minimum closed time [32]
and/or the Relay off delay [32] settings).
Setting Set relay value (setting 28) Clear relay value (setting 29)
Default 0°C 0°F 0°C 0°F
Range -40 – +99°C -40 – +210°F -40 – +99°C -40 – +210°F
Step size 1°C 1°F 1°C 1°F
7.3.12. Mid voltage relay
This setting is available if the aux input has been set to “Mid point”, see
the Aux input [40] setting.
See the chapter Midpoint voltage monitoring [46] for more information about
the midpoint voltage.
When the midpoint voltage deviation rises above the “set relay” value, the
relay will close.
When the midpoint voltage deviation falls below the “clear relay” value, the
relay will open (after a delay, depending on the Relay minimum closed time
[32] and/or the Relay off delay [32] settings).
Setting Set relay value (setting 30) Clear relay value (setting 31)
Default 0% 0%
Range 0 – 99% 0 – 99%
Step size 1% 1%
7.4. Alarm settings
The BMV battery monitor is equipped with an alarm relay and a buzzer. Alarms
are also visible on the VictronConnect app while connected to the battery
monitor or are used to send an alarm signal to a GX device.
Alarms are disabled by default. To enable do the following:
· In the VictronConnect app, enable the alarm by sliding the slider button to
the right.
· Via the head unit, enable the alarm by changing the “set” and “clear” value
in the alarm settings to any value above zero.
7.4.1. Alarm buzzer
When enabled (set to ON), the buzzer will sound an alarm as soon as an alarm
condition occurs. After a button is pressed, the buzzer will stop sounding.
When disabled (set to OFF) the buzzer will not sound an alarm.
Setting Alarm buzzer (setting 32)
Default ON
Modes ON OFF
7.4.2. Low SoC alarm settings
When enabled, the alarm will activate when the state of charge (SoC) falls
below the set value for more than 10 seconds. The alarm will deactivate when
the state of charge rises above the clear value
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Setting Set alarm value (setting 33) Clear alarm value (setting 34)
Manual – BMV-712 Smart
Default 1% 1%
Range 0 – 100% 0 – 100%
Steps 1% 1%
7.4.3. Low voltage alarm
When enabled, the alarm will activate when the battery voltage falls below the
set value for more than 10 seconds. The alarm will deactivate when the battery
voltage rises above the clear value.
Setting Set alarm value (setting 35) Clear alarm value (setting 36)
Default 1.1V 1.0V
Range 0 – 95.0V 0 – 95.0V
Steps 0.1V 0.1V
7.4.4. High voltage alarm
When enabled, the alarm will activate when the battery voltage rises above the
set value for more than 10 seconds. The alarm will deactivate when the battery
voltage drops below the clear value.
Setting Set alarm value (setting 37) Clear alarm value (setting 38)
Default 1.1V 1.0V
Range 0 – 95.0V 0 – 95.0V
Steps 0.1V 0.1V
7.4.5. Low starter voltage alarm
This setting is only available if the Aux input has been set to “Starter
battery”, see chapter Aux input [40].
When enabled, the alarm will activate when the starter battery voltage falls
below the set value for more than 10 seconds. The alarm will deactivate when
the starter battery voltage rises above the clear value.
Setting Set alarm value (setting 39) Clear alarm value (setting 40)
Default 1.1V 1.0V
Range 0 – 95.0V 0 – 95.0V
Steps 0.1V 0.1V
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7.4.6. High starter voltage alarm
This setting is only available if the Aux input has been set to “Starter
battery”, see chapter Aux input [40].
When enabled, the alarm will activate when the starter battery voltage rises
above the set value for more than 10 seconds and the alarm will deactivate
when the starter battery voltage drops below the clear value.
Setting Set alarm value (setting 41) Clear alarm value (setting 42)
Default 1.1 V 1.0 V
Range 0 – 95.0V 0 – 95.0V
Steps 0.1V 0.1V
7.4.7. High temperature alarm
This setting is only available if the Aux input has been set to “temperature”,
see chapter Aux input [40].
When enabled, the alarm will activate when the battery temperature rises above
the set value for more than 10 seconds. The alarm will deactivate when the
battery temperature drops below the clear value.
Setting Set relay value (setting 43) Clear relay value (setting 44)
Default 0°C 0°F 0°C 0°F
Range -40 – +99°C -40 – +210°F -40 – +99°C -40 – +210°F
Step size 1°C 1°F 1°C 1°F
7.4.8. Low temperature alarm
This setting is only available if the Aux input has been set to “temperature”,
see chapter Aux input [40].
When enabled, the alarm will activate when the battery temperature falls below
the set value for more than 10 seconds. The alarm will deactivate when the
battery temperature rises above the clear value.
Setting Set relay value (setting 45) Clear relay value (setting 46)
Default 0°C 0°F 0°C 0°F
Range -40 – +99°C -40 – +210°F -40 – +99°C -40 – +210°F
Step size 1°C 1°F 1°C 1°F
7.4.9. Midpoint deviation alarm
This setting is only available if the Aux input has been set to “Midpoint”;
see chapter Aux input [40].
When enabled, the alarm will activate when the midpoint voltage deviation
rises above the set value for more than 10 seconds. The alarm will deactivate
when the midpoint voltage deviation drops below the clear value.
Setting Set alarm value (setting 47) Clear alarm value (setting 48)
Default 2 % 1 %
Range 0 – 99 % 0 – 99 %
Steps 1 % 1 %
7.5. Display settings
7.5.1. Backlight intensity
The intensity of the backlight This setting ranges from 0 (always off) to 9
(maximum intensity).
Setting Backlight intensity (setting 49)
Default 5
Range 0 – 9
Step size 1
7.5.2. Backlight always on
When set the backlight will not automatically turn off after 60 seconds of
inactivity.
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Setting Backlight always on (setting 50)
Default OFF
7.5.3. Scroll speed
The scroll speed of the display. This setting ranges from 1 (very slow) to 5
(very fast).
Setting Scroll speed (setting 51)
Default 2
Range 1 – 5
7.5.4. Main voltage display
Must be set to ON to display the voltage of the main battery in the monitoring
menu.
Setting
Default
Main voltage display (setting 52)
ON
7.5.5. Current display
Must be set to ON to display the current in the monitoring menu.
Setting
Default
Current display (setting 53)
ON
7.5.6. Power display
Must be set to ON to display the power measurement in the monitoring menu.
Setting
Default
Power display (setting 54)
ON
7.5.7. Consumed Ah display
Must be set to ON to display the consumed Ah in the monitoring menu.
Setting
Default
Consumed Ah display (setting 55)
ON
7.5.8. State of charge display
Must be set to ON to display the battery state of charge in the monitoring
menu.
Setting State of charge display (setting 56)
Default 5
7.5.9. Time-to-go display
Must be set to ON to display the state of charge in the monitoring menu.
Setting
Default
Time-to-go display (setting 57)
ON
Range 1 – 5
Modes ON OFF
Step size 1
Modes ON OFF
Modes ON OFF
Modes ON OFF
Modes ON OFF
Step size 1
Modes ON OFF
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7.5.10. Starter voltage display
Must be set to ON to display the auxiliary voltage in the monitoring menu.
Setting
Default
Starter voltage display (setting 58)
ON
7.5.11. Temperature display
Must be set to ON to display the battery temperature in the monitoring menu.
Setting
Default
Temperature display (setting 59)
ON
7.5.12. Mid-voltage display
Must be set to ON to display the midpoint deviation percentage in the
monitoring menu.
Setting
Default
Mid-voltage display (setting 60)
ON
Modes ON OFF
Modes ON OFF
Modes ON OFF
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7.6. Miscellaneous settings
7.6.1. Software version
Setting 61
This is a read-only setting. it displays the firmware version of the battery
monitor.
The software version as displayed on the head unit is the same as the firmware
version as displayed in the VictronConnect app product settings. In addition
to this, the VictronConnect app also allows updating of the firmware. For more
information see the Firmware [42] setting.
Setting Software version (setting 61)
Default
Displays the battery monitor firmware version.
Mode Read-only
7.6.2. Restore defaults
Setting 62 This head unit setting resets all settings to factory default. The
defaults can also be restored via the VictronConnect app. For more information
on how to do this see the Reset to defaults [43] chapter. To restore defaults
do the following: · Navigate to setting 62: the text “restore defaults” is
displayed
· Press SELECT on the head unit: the blinking text “reset” is displayed.
· Press SELECT again: a beep is heard, and all settings have gone back to
factory default.
· Should the reset function have been entered accidentally and the text
“reset” is blinking, press SETUP to leave and go back to the regular settings
menu.
Note that restoring the defaults does not clear the history settings. To clear
the history see the Clear history [39] setting. When in normal operating mode,
the factory settings can also be restored by pressing SETUP and SELECT
simultaneously for 3 seconds on the head unit. Note that this is only possible
if the Lock setup [39] setting is off.
7.6.3. Clear history
Setting 63 This setting resets all settings to factory default. To clear the
history do the following: · Navigate to setting 63: the text “clear history”
is displayed
· Press SELECT on the head unit: the blinking text “clear” is displayed.
· Press SELECT again: a beep is heard and all settings have gone back to
factory default.
· Should the reset function have been entered accidentally and the text
“clear” is blinking, press SETUP to leave and go back to the regular settings
menu.
The history can also be cleared via the VictronConnect app, for more
information on how to do this see the Reset history [41] chapter.
Please be aware that history data is an important tool to keep track of
battery performance and is also needed to diagnose possible battery problems.
Do not clear the history unless the battery bank is replaced.
7.6.4. Lock setup
When on, all settings (except this one) are locked (read-only) and cannot be
altered via the head unit. Note that they still can be altered via the
VictronConnect app.
Setting Lock setup (setting 64)
Default OFF
ON/OFF
Modes
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7.6.5. Shunt current
When a shunt other than the one supplied with the battery monitor is used, use
this setting to set the rated current of the shunt.
Setting Shunt current (setting 65)
Default 500A
Range 1 – 9999A
Step size 1A
7.6.6. Shunt voltage
When a shunt other than the one supplied with the battery monitor is used, use
this setting to change the rated voltage of the shunt.
Setting Shunt voltage (setting 66)
Default 50mV
Range 1 – 75mV
Step size 1mV
7.6.7. Temperature unit
This setting is available if the aux input has been set to “Temperature”, see
the Aux input [40] setting.
Use this setting to select the temperature unit the battery monitor head unit
is using.
Note that this setting only affects the battery monitor head unit display and
settings. To change the temperature unit in the VictronConnect app see
Temperature unit setting [41].
Setting Temperature unit (setting 67)
Default CELC
Modes CELC/FAHR
7.6.8. Temperature coefficient
This setting is available if the aux input has been set to “Temperature”, see
the Aux input [40] setting.
The available battery capacity decreases with temperature. The temperature
coefficient (delta T) is the percentage the battery capacity changes with
temperature when temperature decreases to less than 20°C (above 20°C the
influence of temperature on capacity is relatively low and is not taken into
account). Typically, the reduction, compared to the capacity at 20°C, is 18%
at 0°C and 40% at -20°C.
The unit of this value is “%cap/°C” or per cent capacity per degree Celsius.
The typical value (below 20°C) is 1%cap/°C for lead acid batteries, and
0.5%cap/°C for LFP batteries.
Setting Temperature coefficient (setting 68)
Default 0.0%cap/°C 0.0%cap/°F
Range 0 – 2.0%cap/°C 0 – 3.6%cap/°F
Step size 0.1%cap/°C 0.1%cap/°F
7.6.9. Aux input
This setting sets the function of the auxiliary input. Select between: None,
Starter battery, Midpoint or Temperature.
Setting Aux input (setting 69)
Default NONE
Modes NONE START MID
TEMP
Description Disables the auxiliary input. Auxiliary voltage, e.g. a starter battery Midpoint voltage Battery temperature. Note that a special temperature sensor is needed. For more information see: Auxiliary connection for temperature monitoring [9]
7.6.10. Battery starts synchronised
Note that if the battery monitor settings are accessed via the head unit, this
setting will be part of the miscellaneous setting, and if accessed via
VictronConnect it will be part of the battery settings.
For full information about this setting see the Battery starts synchronised
[30] chapter.
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Setting Start synchronized (setting 70)
Default ON
Modes ON/OFF
7.6.11. Bluetooth mode
Determines whether to enable Bluetooth. If turned OFF using the VictronConnect
app, the Bluetooth functionality is not disabled until disconnected from the
BMV.
Setting Bluetooth mode (setting 71)
Default ON
ON/OFF
Modes
7.6.12. Monitor Mode
Setting 72 If you wish to use the battery monitor to monitor individual DC
circuits rather than as a whole-of-system battery monitor, you can change the
“Monitor mode” setting in the “Misc” menu from “Battery Monitor” to “DC Energy
Meter”.
If “DC meter” is selected, you can select the following types:
Solar charger, Wind charger, Shaft generator, Alternator, Fuel cell, Water
generator, DC-DC charger, AC charger, Generic source, Generic load, Electric
drive, Fridge, Water pump, Bilge pump, DC system, Inverter, Water heater.
When connected to a GX device, the type, the current and the power is shown in
the user interface, and this information is also available on the VRM Portal.
When the GX device is also configured as type “has DC System”, the GX does
more than just recording and visualisation:
1. The power shown in the DC system box is the sum of power reported by all
battery monitors configured as such. Having multiple meters can be useful, for
example, in a catamaran, so that the DC systems in the port hull and in the
starboard hull are being measured.
2. The DC system current is being compensated for when setting DVCC charge
current limits to inverter/chargers and solar chargers. For example, when a
load of 50A is being measured, and CCL by the battery is 25A, the limit given
to the inverter/ charger or solar charger is 75A.
See the GX device documentation for more information about these advanced
features, especially refer to the Distributed voltage and current control
chapter.
7.7. Additional settings
These VictronConnect settings are not located in the VictronConnect settings
menu but are located elsewhere in the VictronConnect app.
7.7.1. Reset history
This setting can be found at the bottom of the history tab.
This setting can also be made via the head unit. For more information see the
Clear history [39]chapter.
Please be aware that history data is an important tool to keep track of
battery performance and is also needed to diagnose possible battery problems.
Do not clear the history unless the battery bank is replaced.
7.7.2. Reset PIN code
Note that the PIN code is only applicable when connecting to the battery
monitor via Bluetooth.
This setting can be found in the settings of the VictronConnect app itself.
Leave the battery monitor by clicking on the arrow. This will bring you back
to the device list of the VictronConnect app. Now, click on the menu symbol
next to the battery monitor listing.
A new window will open which allows you to reset the PIN code back to its
default: 000000. To be able to reset the PIN code you will need the enter the
battery monitor unique PUK code. The PUK code is printed on the product
information sticker on the Battery monitor.
7.7.3. Temperature unit setting
This setting can be found in the settings of the VictronConnect app itself.
Leave the battery monitor page by clicking on the arrow. This will bring you
back to the device list of the VictronConnect app. Click on the menu symbol
and then click on the
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settings symbol. Here you can select the “Display temperature unit”. Selecting
Celsius will display the temperature in °C and selecting Fahrenheit will
display the temperature in °F.
7.7.4. Serial number
The serial number can be found in the battery monitor product info section of
the VictronConnect app or on the product information sticker rear of the
battery monitor head unit.
7.7.5. Disabling and re-enabling Bluetooth
Bluetooth is enabled by default in the battery monitor. If Bluetooth is not
wanted it can be disabled. This is done by sliding the Bluetooth switch in the
product settings. A reason to disable Bluetooth could be for security reasons,
or to eliminate unwanted transmission from the Battery monitor. As soon as
Bluetooth has been disabled the only way to communicate with the battery
monitor is via its VE.Direct port. This is done via the USB to VE.Direct
interface or via a GX device connected to the battery monitor via a VE.Direct
cable or the USB to VE.Direct interface. For more info see the VictronConnect
app via USB [25] chapter. Bluetooth can be re-enabled by connecting to the
battery monitor with VictronConnect via the VE.Direct USB interface. Once
connected you can navigate to the product settings menu and re-enable
Bluetooth. For more information also see the VictronConnect manual.
VictronConnect product info screen.
7.7.6. Changing PIN code
In the battery monitor Bluetooth interface product info the PIN code can be
changed.
7.7.7. Custom name
In the battery monitor product information screen, you can change the name of
the battery monitor. By default, it is called by its product name. But a more
applicable name might be needed, especially if you are using multiple battery
monitors in close proximity of each other it might become confusing with which
battery monitor you are communicating. You can, for example, add
identification numbers to their name, like: Battery Monitor A, Battery Monitor
B and so on.
7.7.8. Firmware
Both the battery monitor and its Bluetooth interface run on firmware.
Occasionally a newer firmware version is available. New firmware is released
to either add features or to fix a bug. The product overview in the
VictronConnect app displays the battery monitor and the Bluetooth interface
firmware version. It also indicates whether the firmware is the latest
version, and there is a button you can press to update the firmware.
On the first installation, it is always recommended to update to the most
recent firmware (if available). Whenever you connect to the battery monitor
with an up-to-date version of the VictronConnect app, it will check the
firmware, and if there is a newer version available, it will ask you to update
the firmware. The VictronConnect app contains the actual firmware files, so an
internet connection is not needed to update to the most recent firmware as
long as you are using the most up-to-date version of the VictronConnect app.
A firmware update is not mandatory. If you choose not to update the firmware,
you can only read out the battery monitor, but you cannot change settings.
Settings can only be changed if the battery monitor runs on the most recent
firmware.
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For more information on firmware updates also see the VictronConnect app
manual Firmware update chapter. This setting is also available via the head
unit Software version [39] setting. But note that this is a read-only setting.
The firmware cannot be updated via the head unit.
7.7.9. Reset to defaults
To set all settings back to default select “Reset to defaults”. Please note
that this only resets all settings to their default values, the history is not
reset. This setting is also available via the head unit. For more information
see the Restore defaults [39] chapter.
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8. Battery capacity and Peukert exponent
Battery capacity is expressed in Amp hour (Ah) and indicates how much current
a battery can supply over time. For example, if a 100Ah battery is being
discharged with a constant current of 5A, the battery will be totally
discharged in 20 hours. The rate at which a battery is being discharged is
expressed as the C rating. The C rating indicates how many hours a battery
with a given capacity will last. 1C is the 1h rate and means that the
discharge current will discharge the entire battery in 1 hour. For a battery
with a capacity of 100Ah, this equates to a discharge current of 100A. A 5C
rate for this battery would be 500A for 12 minutes (1/5 hours), and a C5 rate
would be 20A for 5 hours.
There are two ways of expressing the C rating of a battery. Either with a
number before the C or with a number after the C. For example: · 5C is the
same as C0.2 · 1C is the same as C1 · 0.2C is the same as C5
The capacity of a battery depends on the rate of discharge. The faster the
rate of discharge, the less capacity will be available. The relation between
slow or fast discharge can be calculated by Peukert’s law and is expressed by
the Peukert exponent. Some battery chemistries suffer more from this
phenomenon than others. Lead acid are more affected by this than lithium
batteries are. The battery monitor takes this phenomenon into account with
Peukert exponent. Discharge rate example A lead acid battery is rated at 100Ah
at C20, this means that this battery can deliver a total current of 100A over
20 hours at a rate of 5A per hour. C20 = 100Ah (5 x 20 = 100). When the same
100Ah battery is discharged completely in two hours, its capacity is greatly
reduced. Because of the higher rate of discharge, it may only give C2 = 56Ah.
Peukert’s formula The value which can be adjusted in Peukert’s formula is the
exponent n: see the formula below. In the battery monitor the Peukert exponent
can be adjusted from 1.00 to 1.50. The higher the Peukert exponent the faster
the effective capacity `shrinks’ with increasing discharge rate. An ideal
(theoretical) battery has a Peukert exponent of 1.00 and has a fixed capacity
regardless of the size of the discharge current. The default setting in the
battery monitor for the Peukert exponent is 1.25. This is an acceptable
average value for most lead acid batteries. Peukert’s equation is stated
below: Cp = In x t Where Peukert’s exponent n is:
To calculate the Peukert exponent you will need two rated battery capacities.
This is usually the 20h discharge rate and the 5h rate, but can also be the
10h and 5h, or the 20h and the 10h rate. Ideally use a low discharge rating
together with a substantially higher rating. Battery capacity ratings can be
found in the battery datasheet. If in doubt contact your battery supplier.
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Battery capacity and Peukert exponent
Manual – BMV-712 Smart Calculation example using the 5h and the 20h rating The
C5 rating is 75Ah. The t1 rating is 5h and I1 is calculated:
The C20 rating is 100Ah. The t2 rating is 20h and I2 is calculated:
The Peukert exponent is:
A Peukert calculator is available at http://www.victronenergy.com/ support-
and-downloads/software#peukert-calculator.
Please note that the Peukert exponent is no more than a rough approximation of
reality. In case of very high currents, the battery will give even less
capacity than predicted by a fixed exponent. We do not recommend changing the
default value in the battery monitor, except in the case of lithium batteries.
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9. Midpoint voltage monitoring
One bad cell or one bad battery can destroy a large, expensive battery bank. A
short circuit or high internal leakage current in one cell for example will
result in undercharge of that cell and overcharge of the other cells.
Similarly, one bad battery in a 24V or 48V bank of several series/parallel
connected 12V batteries can destroy the whole bank. Moreover, when new cells
or batteries are connected in series, they should all have the same initial
state of charge. Small differences will be ironed out during absorption or
equalize charging, but large differences will result in damage during charging
due to excessive gassing of the cells or batteries with the highest initial
state of charge. A timely alarm can be generated by monitoring the midpoint of
the battery bank (i.e. by splitting the string voltage in half and comparing
the two string voltage halves). The midpoint deviation will be small when the
battery bank is at rest, and will increase: · At the end of the bulk phase
during charging (the voltage of well charged cells will increase rapidly while
lagging cells still need
more charging). · When discharging the battery bank until the voltage of the
weakest cells starts to decrease rapidly. · At high charge and discharge
rates.
9.1. Battery bank and midpoint wiring diagrams
9.1.1. Connecting and monitoring midpoint in a 24V battery bank
GOOD: The midpoints are not connected and without busbars or midpoint monitoring.
WRONG: The midpoints are connected and without busbars or midpoint monitoring.
Due to the voltage drop over the positive and the negative cables the midpoint
voltage is not identical.
In an unmonitored battery bank, the midpoints should not be interconnected;
since one bad battery bank can go unnoticed and could damage all other
batteries.
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GOOD: The midpoints are not connected; busbars are used but without midpoint monitoring.
GOOD: The midpoints are connected, with busbars and midpoint monitoring.
Always use busbars when applying midpoint voltage monitoring. The cables to the busbars must all have the same length. The midpoints can only be connected if corrective action is taken in case of an alarm.
9.1.2. Connecting and monitoring midpoint in a 48V battery bank
GOOD: The midpoints are not connected and without busbars or midpint monitoring.
WRONG: The midpoints are connected and without busbars or midpoint monitoring.
Due to the voltage drop over the positive and the negative cables the midpoint voltage is not identical.
GOOD: The midpoints are not connected; busbars are used and without midpoint monitoring.
GOOD: The midpoints are connected, busbars are used and with midpoint monitoring.
In an unmonitored battery bank the midpoints should not be interconnected, one
bad battery bank can go unnoticed and could damage all other batteries.
Always use busbars when applying midpoint voltage monitoring. The cables to
the busbars must all have the same length.
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Midpoints can only be connected if corrective action is taken in case of an
alarm.
9.2. Midpoint deviation calculation
The battery monitor measures the midpoint and then calculates the deviation in
a percentage from what the midpoint should be.
Where: d is the deviation in % Vt is the top string voltage Vb is the bottom
string voltage V is the voltage of the battery (V = Vt + Vb)
9.3. Setting the alarm level
In case of VRLA (gel or AGM) batteries, gassing due to overcharging will dry
out the electrolyte, increasing internal resistance and ultimately resulting
in irreversible damage. Flat plate VRLA batteries start to lose water when the
charge voltage approaches 15V (12V battery). Including a safety margin, the
midpoint deviation should therefore remain below 2% during charging. When, for
example, charging a 24V battery bank at 28.8V absorption voltage, a midpoint
deviation of 2% would result in:
Obviously, a midpoint deviation of more than 2% will result in overcharging
the top battery and undercharging the bottom battery. These are two good
reasons to set the midpoint alarm level at not more than d = 2%.
This same percentage can be applied to a 12V battery bank with a 6V midpoint.
In case of a 48V battery bank consisting of 12V series connected batteries,
the % influence of one battery on the midpoint is reduced by half. The
midpoint alarm level can therefore be set at a lower level.
9.4. Alarm delay
An alarm delay is in place to prevent the occurrence of alarms during short-
term deviations that will not damage a battery. The alarm is triggered when
the deviation exceeds the set alarm value for more than 5 minutes. If the
deviation exceeds the set alarm value by a factor of two or more, the alarm
will trigger after 10 seconds.
9.5. What to do in case of an alarm during charging
In case of a new battery bank the alarm is usually due to differences in the
initial state of charge of the individual battery. If the deviation increases
to more than 3% you should stop charging the battery bank and charge the
individual batteries or cells separately. Another way is to substantially
reduce the charge current to the battery bank, this will allow the batteries
to equalize over time.
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If the problem persists after several charge-discharge cycles do the
following: · In case of series/parallel connection disconnect the midpoint,
parallel connection wiring and measure the individual midpoint
voltages during absorption charging to isolate batteries or cells which need
additional charging.
· Charge and then test all batteries or cells individually.
In case of an older battery bank which has performed well in the past the
problem may be due to systematic undercharge. In this case more frequent
charging or an equalization charge is needed. Please note that only flooded
deep cycle flat plate or OPzS batteries can be equalized. Better and regular
charging will solve the problem. In case there are one or more faulty cells: ·
In case of series/parallel connection disconnect the midpoint, parallel
connection wiring and measure the individual midpoint
voltages during absorption charging to isolate batteries or cells which need
additional charging.
· Charge and then test all batteries or cells individually.
9.6. What to do in case of an alarm during discharging
The individual batteries or cells of a battery bank are not identical, and
when fully discharging a battery bank, the voltage of some cells will start
dropping earlier than others. The midpoint alarm will therefore nearly always
trip at the end of a deep discharge. If the midpoint alarm trips much earlier
(and does not trip during charging), some batteries or cells may have lost
capacity or may have developed a higher internal resistance than others. The
battery bank may have reached the end of service life, or one or more cells or
batteries have developed a fault: · In case of series/parallel connection,
disconnect the midpoint parallel connection wiring and measure the individual
midpoint
voltages during discharging to isolate faulty batteries or cells.
· Charge and then test all batteries or cells individually.
9.7. The Battery Balancer
A consideration can be made to add a Battery Balancer to the system. A Battery
Balancer will equalize the state of charge of two series connected 12V
batteries, or of several parallel strings of series connected batteries. When
the charge voltage of a 24V battery system increases to more than 27.3V, the
Battery Balancer will turn on and compare the voltage over the two series
connected batteries. The Battery Balancer will draw a current of up to 0.7A
from the battery (or parallel connected batteries) with the highest voltage.
The resulting charge current differential will ensure that all batteries will
converge to the same state of charge. If needed, several balancers can be
paralleled. A 48V battery bank can be balanced with three Battery Balancers,
one between each battery. For more information see the Battery Balancer
product page: https://www.victronenergy.com/batteries/battery-balancer.
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10. Troubleshooting
10.1. Functionality issues
10.1.1. Unit is dead
On first connection the display of the head unit should be active. If this is
not the case check the fuse in the +B1 cable and also check the cable itself
and its terminals. In case the temperature sensor is used: · The temperature
sensor M8 cable lug must be connected to the positive pole of the battery bank
(the red wire of the sensor
doubles as the power supply wire). · Check the fuse in the positive (red)
cable. · Make sure the correct temperature sensor is used. Note that the
MultiPlus temperature sensor is not suitable. · Make sure the temperature
sensor has been connected the right way. The red cable should connect the +B1
terminal and the
black wire to the +B2 terminal. See the Auxiliary connection for temperature
monitoring [9] chapter for connection instructions and a wiring diagram.
10.1.2. Auxiliary port not working
Check the fuse in the +B2 cable and also check the cable itself and its
terminals. In case a second battery (starter battery) is monitored: Make sure
the second battery negative is connected to the load side of the battery
monitor shunt. See the chapter Auxiliary connection for monitoring the voltage
of a second battery [8] for connection instructions and a wiring diagram. In
case the temperature sensor is used: · The temperature sensor M8 cable lug
must be connected to the positive pole of the battery bank (the red wire of
the sensor
doubles as the power supply wire). · Check the fuse in the positive (red)
cable. · Make sure the correct temperature sensor is used. The MultiPlus
temperature sensor does not work with the battery monitor. · Make sure the
temperature sensor has been connected the right way. The red cable should
connect to the +B1 terminal and
the black wire to the Aux+B2 terminal. See the Auxiliary connection for
temperature monitoring [9] chapter for connection instructions and a wiring
diagram.
10.1.3. Unable to change VictronConnect settings
Settings can only be changed if the battery monitor is running on the most up
to date firmware. Update to the latest firmware with the VictronConnect app.
10.2. Connection issues
10.2.1. Cannot connect via Bluetooth
It is highly unlikely that the Bluetooth interface is faulty. Some pointers to
try before seeking support: · Is the battery monitor powered up? The display
on the head unit should be active. If not see the Unit is dead [50] chapter. ·
Is another phone or tablet already connected to the battery monitor? Only one
phone or tablet can be connected to the battery
monitor at any given time. Make sure no other devices are connected and try
again. · Is the VictronConnect app up to date? · Are you close enough to the
battery monitor? In an open space, the maximum distance is about 20 meters. ·
The shunt and the electric cables do negatively influence the range of the
Bluetooth signal. The resulting range of 10-15 meters
is however satisfactory in most cases. The proximity of other electrically
conducting elements, such as the metal chassis of a vehicle or seawater around
the hull of a boat, may reduce the range of the Bluetooth signal to an
unacceptable level. The
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solution in such a case is to add a VE.Direct Bluetooth Dongle (ASS030536011)
to the system, and switch off Bluetooth in the BMV-712 Smart. Be aware that
the VE.Direct Bluetooth Dongle will not support stored trends, Bluetooth GATT
service and the Keep SOC option. · Are you using the Windows version of the
VictronConnect app? This version is unable to connect via Bluetooth. Use
Android, iOS or macOS instead (or use the USB – VE.Direct interface). For
connection issues, see the troubleshooting section of the VictronConnect
manual: https://www.victronenergy.com/live/ victronconnect:start.
10.2.2. PIN code lost
Note that the PIN code is only applicable when connecting to the battery
monitor via Bluetooth. If you have lost the PIN code you will need to reset
the PIN code to its default PIN code, see the Reset PIN code [41] chapter.
More information and specific instructions can be found in the VictronConnect
manual: https://www.victronenergy.com/live/ victronconnect:start.
10.3. Incorrect readings
10.3.1. Charge and discharge current are inverted
The charge current should be shown as a positive value. For example: 1.45A.
The discharge current should be shown as a negative value. For example:
-1.45A. If the charge and discharge currents are reversed, the negative power
cables on the battery monitor must be swapped.
10.3.2. Incomplete current reading
The negatives of all the loads and the charge sources in the system must be
connected to the system minus side of the shunt.
If the negative of a load or a charge source is connected directly to the
negative battery terminal or the “battery minus” side on the shunt, their
current will not flow through the battery monitor and will be excluded from
the overall current reading and the state of charge reading.
The battery monitor will display a higher state of charge than the actual
state of charge of the battery.
10.3.3. There is a current reading while no current flows
If there is a current reading while no current is flowing through the battery
monitor, perform a zero current calibration [31] while all loads are turned
off or set the current threshold [30].
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10.3.4. Incorrect state of charge reading
An incorrect state of charge can be caused by a variety of reasons. Incorrect
battery settings The following parameter(s) will have an effect on the state
of charge calculations if they have been set up incorrectly: · Battery
capacity.
· Peukert exponent.
· Charge efficiency factor.
Incorrect state of charge due to a synchronisation issue: The state of charge
is a calculated value and will need to be reset (synchronised) every now and
then. The synchronisation process is automatic and is performed each time the
battery is fully charged. The battery monitor determines that the battery is
fully charged when all 3 “charged” conditions have been met. The “charged”
conditions are: · Charged voltage (Voltage).
· Tail current (% of battery capacity).
· Charge detection time (minutes).
A practical example of the conditions that need to be met before a
synchronisation will take place: · The battery voltage has to be above 13.8V.
· The charge current has to be less than 0.04 x battery capacity (Ah). For a
200Ah battery, this is 0.04 x 200 = 8A.
· Both above conditions have to be stable for 3 minutes.
If the battery is not fully charged or if the automatic synchronisation does
not happen, the state of charge value will start to drift and will eventually
not represent the actual state of charge of the battery. The following
parameter(s) will have an effect on automatic synchronisation if they have
been set incorrectly: · Charged voltage.
· Tail current.
· Charged detection time.
· Not occasionally fully charging the battery.
For more information on these parameters see the chapter: “Battery settings”.
Incorrect state of charge due to incorrect current reading: The state of
charge is calculated by looking at how much current flows in and out of the
battery. If the current reading is incorrect, the state of charge will also be
incorrect. See paragraph Incomplete current reading [51].
10.3.5. State of charge is missing
This means that the battery monitor is in an unsynchronised state. This can
occur when the battery monitor has just been installed or after it has been
unpowered for some time and is being powered up again. To fix this, fully
charge the battery. Once the battery is
References
- victronconnect:start [Victron Energy]
- Manual - BMV-712 Smart
- 11. DVCC - Distributed Voltage and Current Control
- 1. Introduction
- 9. Firmware updates
- 10. VictronConnect-Remote (VC-R) – Configuration and monitoring via VRM