interface BX6-BT 6-Channel Bluetooth Measuring Amplifier Instruction Manual

Model BX6-BT 6-Channel
Bluetooth® Measuring Amplifier

Operation manual

BX6-BT 6-Channel Bluetooth Measuring Amplifier

BX6-BT

BX6-BT-OEM

Measuring amplifier BX6-BT and BX6-BT-OEM

6-channel measuring amplifier
Operation via Li-Ion battery 3.6V ….. V
Integrated battery charging circuit
Inputs configurable for full, half, quarter bridges, 350-1000 ohms, 0 ……… V
1x Bluetooth 4.0 (LE) (GATT) or Bluetooth Classic (SPP) configurable, Data logger function with SD Card up to 7x 2000 measured values/s
Real Time Clock
Transmit measured value: 6x 1 measured values/s……. 500 measured values/s
Simultaneous acquisition of channels 1 to 3 and 2 to 6
Resolution <100 nV / V
Independent calculation of the 3 forces and torques for 6-axis sensors
Reading TEDS data on channel 1 counter / frequency / speed measurement on channel 7
Two operating hours counters, one absolute and one resettable

Description

The BX6-BT is a 6-channel measuring amplifier with Bluetooth interface and data logger function. There are two different model variants available: The module BX6-BT- OEM with solder pads and the version BX6-BT with housing.

The dimensions of the module are only 50mm x 20mm x 17mm. The BX6-BT-OEM has gold-plated solder pads for connecting the sensors, the battery and other I/O functions. For connection, strands with a cross-section of up to 0.09mm² (AWG28) are suitable.

The version BX6-BT has the same functionality, but all connections are done by terminal strips and a rechargeable battery is build-in. The charging circuit can be powered by  a supply voltage from 5V to 28VDC.

Both BX6-BTmodels have 6 measuring channels, of which the first channel is for bridge strain gauges, while channels 2 to 6 can be individually configured as voltage input  (singleended) or as strain gauge bridge inputs. All channels can be connected as full- half or quarterbridge configuration.

Another seventh channel for acquiring digital pulses is available for connecting incremental encoders or as an input for square wave signals.
The number of channels in the data transmission and file logging is configurable from 1 to 7 channels. Channel 7 is reserved for the connection of incremental encoders.
Channel 1 supports the reading of TEDS memories to automatically configure the scaling factor for the connected sensor. In addition, two configurable threshold outputs are available.
The Bluetooth connection supports BT Classic with Serial Port Profile (SPP) for complete configuration and continuous messaging, and BT LowEnergy (LE) with some  services (GATT) for reading measurement data and battery voltage, e.g. via smartphone.
The measurement data can be recorded on a micro SD memory card, whereby there are various configuration options, such as continuous recording up to 3000 readings per  second, long recording intervals with power management (battery saving mode) and digital input triggered recording. The recorded files can also be downloaded via  Bluetooth SPP. A real-time clock creates timestamps in real time in the measurement data files.

More functions

• The connected 3.7V lithium-ion battery can be charged by an integrated charging circuit.

• The temperature in the device and the battery voltage can be measured

• The simultaneous zeroing of all channels can be triggered via a digital input („tare“).

• The BX6-BT is protected against vibration by a full encapsulation in a plastic housing.

• The configuration and acquisition of measurement data is possible with the program BlueDAQ in the mode “BT Classic” with Serial Port Profile (SPP)

• The integrated Bluetooth module has its own microcontroller, which offers the self-programming user a simple scripting language to implement their own embedded applications. All functions of the BX6 CPU and all supported BT services as well as additional digital outputs and a dedicated LED are available.
  The factory-installed “BGscript” script serves the BT-LE requests and some SPP commands needed to perform the functionality described here. Communication with the BX6-6CPU is forwarded transparently.

• With the help of the microcontroller in the Bluetooth module, the BT transmission power and various power-on/off and battery saving modes can be set and the battery voltage can also be read out.

Software / Communication

First, the BX6-BT must be searched and found (with the battery connected) by the Bluetooth driver of the BT adapter of the PC. The displayed device name of the BX6-6BT  after it has been found is the same as the serial number of the device indicated on the nameplate. Some drivers may need to search manually for the supported services;  SPP (BT classic) and BT-LE are supported.

To use the Windows program BlueDAQ, e.g., for configuration, the BT driver for SPP must create a virtual COM port whose number should be known (otherwise look in  the Windows Device Manager), so that the program can connect to the BX6-BT. Click on the button “Add Channel”.

The BT device search process does not need to be repeated later if the same device is reopened with the same PC, and the COM port number will remain the same. If the  host PC or another BX6-BT is changed, the search must be carried out again.

After connecting to the software or opening the COM port, the BX6-BT is fully turned on, the blue LED that indicates the active BT connection is lit as well as the green  that indicates that the BX6-CPU analog amplifier electronics are on.

With BlueDAQ can be configured among many other things whether the BX6-CPU should remain switched on after closing the BT connection or not. If it is off, this saves  battery charge, if it is on, e. g. the measurement data can be recorded permanently.

This and other Bluetooth-specific settings can be found in the program under:
Menu bar → Device → Advanced Settings → Interface → Bluetooth Settings
Settings for recording can be found here:
Menu bar → Device → Advanced Settings → Administration → Measuring Value Logger → Settings
There you can also open a file browser for the BX6-BT SD card.
BlueDAQ also provides a context help, which can be activated in the main window via Menubar -> Help.
After the first or new connection of the battery (Li-ion battery), the real- time clock should be set. This is especially important when measuring data is to be recorded on an  SD card. When you first turn it on after plugging in a new battery or when it has been recharged and had been completely empty, the red BX6 LED flashes quickly1.
With BlueDAQ, the real-time clock can be set here:
Menu bar → Device → Advanced Settings → Administration
On the right side under “Device RTC time”, click on the “Sync” button next to the date / time display. BlueDAQ can also be used to reset one of the two operating hours  counters at the same location. The operating hours counters work independently of the RTC.
1 it start with device software version 3.17
The functions of the data logger and the frequency / tachometer or counter are described in separate documents which can be acquired by contacting contact@interfacefroce.com.

For self-programming users, a Windows function library (MEGSV8w32.dll) with annotated C header is available for application programming, also with a LabView © library  with wrapper VIs for this DLL.

For the use of the BX6-BT in “Bluetooth LE” mode, a Windows app is available. In the Bluetooth LE mode, the BX6-BT is compatible with general BT-LE/GATT apps, e.g.  for use with mobile phones.

Current consumption

| 59 sec.
GSVonoff=2
Timeintervall>0
Periodical
Logger
seconds| 2 min.
GSVonoff=2
Timeintervall=0
Periodical
Logger
Minutes
---|---|---
BT LE
BTmode=0| GSV off| 1,2 mA| 48 mA| 1,2 mA
GSV on| 53 mA| n.a.| n.a.
BT Classic
SPP
BTmode=1| GSV off| 0,78 mA| 48 mA| 1,2 mA
GSV on| 62,3 mA| n.a.| n.a.

After the mode changed from BT-Classic to BT-LE: 0.78 mA
After the mode changed from BT-LE to BT-Classic: 1.2 mA
The BX6-BT has a built-in battery of 6800 mAh. For example, when logging to SD card with Bluetooth disconnected and data frequency = 10 rows/s (consumption about 60mA), data can be recorded for up to 110 hours.

Sensor connection

To correctly display and record physical values, the measurement amplifier must be configured based on the connected sensor. If the sensor on Channel 1 is equipped with
TEDS and wired properly, it will use the sensor configuration stored in the TEDS data. This includes the system scaling (“AnalogOutScale”), the user scaling and the unit. The usage of TEDS can be deactivated in BlueDAQ under menu bar -> sensor -> TEDS … In this dialog the TEDS data can also be read and displayed.
Sensors without TEDS can be configured with BlueDAQ via the Configuration tab -> Input Type and -> Scaling.

Pin assignment of BX8-BT-OEM

Module Version BX6-BT-OEM
The connection of the sensors, the rechargeable battery and the voltage for charge / trickle charging of the rechargeable battery is done via solder pads.
For the configuration of the inputs to strain gage half bridges or strain gage quarter bridges, solder bridges must be closed.

Pin assignment BX6-BT
The connection of the sensors is done by screw terminals, optional digital I/O connections by push-clamp terminals.

With the push key below, the battery charging state can be checked. With the push key above, the measuring core BX6-CPU can be powered on/off (if configured by software)

Strain gauge full bridges

Strain gauge half bridges

The active strain gauges R3 and R4 are connected to the terminals +Us, +Ud and -Us.
The internal half-bridge R1, R2 is activated with a bridge connection from HB to Ud-.

Strain gauge quarter bridge

The active strain gauge R3 is connected in 3-wire technology to the terminals Ud+, QB and -Us.
The internal half-bridge R1, R2 is activated with a bridge connection from HB to Ud-.

*With BX6-BT, when using quarter bridges of 120 or 1000 Ohms, solder jumper(s) must be changed for the appropriate channel(s). By default, quarter bridge is set to 350 Ohms.
Only one of the three solder jumpers for quarter bridge completion must be closed for each channel, the other two must be left open.

Voltage input UE 0-10V

The analog input UE (single ended) measures voltages 0 … 10V with respect to the US. The potential of US corresponds to the potential of the negative battery voltage.  Single-ended inputs are only available for channels 2-6.2
With BX6-BT, the cable shield can be connected to 1.8, 2.8, … 6.8. With the module version it can be connected to the minus pole of the battery or charging connector (Pad 7).

2 The voltage input is not calibrated

Input for incremental encoder

| BX6-BT-OEM Module| BX6-BT
---|---|---
Designation| Pad No.| Digital I/O No.
Incremental encoder / I_index
(Home/Index/Z)| 4| 10
Incremental encoder / A-signal| 5| 11
Incremental encoder / B-signal| 6| 12
Ground| 26| 6

Battery and charging connector

| BX6-BT-OEM Module| BX6-BT
---|---|---
Designation| Pad No.| Connector
Battery charging connection ground| 7| M8 connector: Blue (3)
Battery charging V+ 4.5 – 5.5V, 0.5A| 8| Not available
Battery charging V+ 5 – 28V, 2A| Not available| M8 connector: Brown (1)
Battery negative pole| 64| (internal only)
Battery positive pole| 65| (internal only)
Tare (Zero Setting, software configurable)
to trigger set zero, connect with GND for
at least 2s| 24| Digital I/O No. 1

Auxiliary voltage supply for active sensors or encoders

| BX6-BT-OEM Module| BX6-BT
---|---|---
Designation| Pad No.| Digital I/O No.
3,3 V Voltage output (10mA max)| 25| 3
GND| 26| 6

Digital inputs and outputs

| BX6-BT-OEM Module| BX6-BT
---|---|---
Designation| Pad No.| Digital I/O No.
Threshold output 2| 37| 5
Threshold output 1| 38| 2
Trigger input| 39| 4
IO_1 / PB4 BT121| 27| 7
IO_2 / PB5 BT121| 40| 8
GND_IO| 41| 6
IO_3 / PB6 BT121 / OnOff Key| 48| –
TEDS communication pin| 51| Channel 1 terminal: 1.7

Function of the LEDs

On/Off, Bluetooth States

When connecting successfully via Bluetooth (classic or BLE) to the BX6-BT, the measuring hardware “BX6-CPU” is always switched on, regardless of the configured on/off  mode or the actual on/off state.

However, the on/off mode of the measuring hardware when the Bluetooth connection is not active, is configurable. With some applications, like recording data on SD card, it’s desirable that the measuring hardware remains on, even with Bluetooth connection closed.
Even in “off” state, the RTC clock remains powered as long as the battery is connected, because in fact, it’s a standby state with current consumption of about 200µA.

saving)
On/Off by Key| 3| ON/OFF BX6-CPU by push key (IO_3), present with M8 version3
On/Off by Switch| 4| ON/OFF BX6-CPU by Switch at IO_3 3

This GSVonOffMode can be changed using BlueDAQ under Menu bar -> Device -> Advanced Settings -> Interface -> Bluetooth Settings. The corresponding BGscript  commands are SetGSVonoff and GetGSVonoff.

The Bluetooth Mode can also be changed between Classic = SPP or LowEnergy (Gatt) in this GSVmulti dialog. When changed, it’s valid after the Program is closed, i.e. after the actual Bluetooth connection is terminated.

Additional Documentation

The communication protocol using Bluetooth Classic (SPP) is generally identical to the serial protocol that is described in BX6-ProtocolDefinitionEN.pdf.
Additionally, the BGscript has some own commands that are separately described in ba-BX6bt-commands.pdf.

Additionally, the BGscript has some own commands that are separately described in ba-BX6bt-commands.pdf.
The communication with the BX6-BT in Bluetooth LowEnergy (Gatt) Mode is described in ba-BX6bt-gattservices_en.pdf

Changelog

Warranty

All instrument products from Interface Inc., (‘Interface’) are warranted against defective material and workmanship for a period of (1) one year from the date of dispatch. If  the ‘Interface’ product you purchase appears to have a defect in material or workmanship or fails during normal use within the period, please contact your Distributor, who  will assist you in resolving the problem. If it is necessary to return the product to ‘Interface’ please include a note stating name, company, address, phone number and a  detailed description of the problem. Also, please indicate if it is a warranty repair. The sender is responsible for shipping charges, freight insurance and proper packaging to  prevent breakage in transit. ‘Interface’ warranty does not apply to defects resulting from action of the buyer such as mishandling, improper interfacing, operation outside of  design limits, improper repair or unauthorized modification. No other warranties are expressed or implied. ‘Interface’ specifically disclaims any implied warranties of  merchantability or fitness for a specific purpose. The remedies outlined above are the buyer’s only remedies. ‘Interface’ will not be liable for direct, indirect, special, incidental  or consequential damages whether based on the contract, tort or other legal theory.

Any corrective maintenance required after the warranty period should be performed by ‘Interface’ approved personnel only.

Interface Inc. ● 7418 East Helm Drive, Scottsdale, Arizona 85260 USA ● Phone 480.948.5555 ●
www.interfaceforce.com ● Email: contact@interfaceforce.com

Read User Manual Online (PDF format)

Download This Manual (PDF format)

Download this manual  >>