tekmar 681 BACnet Snow/Ice Sensor Interface User Manual

: June 6, 2024
: tekmar

Table of Contents

Introduction
BACnet Protocol Implementation Conformance Statement (PICS)
BACNET STANDARDIZED DEVICE PROFILE
BACnet MSTP Connection
BACnet Analog Parameters
BACnet MSTP Troubleshooting
BACnet MSTP Specification
Error Codes
References
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BAS Integration Manual
BACnet Snow/Ice
Sensor Interface 681
IS-T-681-BAS Integration

Introduction

The BACnet Snow/Ice Sensor Interface 681 communicates with a Building Automation System (BAS) using BACnet® MSTP.
This manual provides information about control parameters that can be accessed by building automation or management systems that use BACnet.

BACnet Protocol Implementation Conformance Statement (PICS)

Vendor Name: tekmar Control Systems Ltd.
Vendor ID: 585
Product Name: BACnet Snow/Ice Sensor Interface 681
Product Model Number: 681
Application Software Version: J1297 Firmware Revision: 0.0.2 BACnet Protocol Revision: 14
Product Description:
The 681 is an interface that automatically measures the presence of snow or ice and interfaces with a
Building Automation System through BACnet to operate an automatic snow melting system.

BACNET STANDARDIZED DEVICE PROFILE

BACnet Application Specific Controller (B-ASC)

SUPPORTED BIBBS (ANNEX K)	NAME
DS-RP-B	Data Sharing-ReadProperty-B
DS-RPM-B	Data Sharing-ReadPropertyMultiple-B
DS-WP-B	Data Sharing-WriteProperty-B
DM-DDB-B	Device Management-Dynamic Device Binding-B
DM-DOB-B	Device Management-Dynamic Object Binding-B
DM-DCC-B	Device Management-Device Communication Control-B

SEGMENTATION CAPABILITY	SUPPORTED	WINDOW SIZE
Able to transmit segmented messages	No
Able to receive segmented messages	No

STANDARD OBJECT TYPES SUPPORTED	CREATABLE	DELETABLE
Analog Input	No	No
Analog Value	No	No
Binary Input	No	No
Binary Value	No	No
Device	No	No

DATALINK LAYER	SUPPORTED
BACnet MSTP	Yes

NETWORK SECURITY OPTIONS

Non-secure Device| –

DATALINK LAYER OPTION	SUPPORTED
BACnet MSTP	Yes

DEVICE ADDRESS BINDING OPTION	SUPPORTED
Device Address Binding	NO

BACnet MSTP Connection

SERVICE NAME	INITIATE	EXECUTE
real property	–	Yes
ReadPropertyMultiple	–	Yes
DeviceCommunicationControl	–	Yes
Who-Is	–	Yes
I-Am	Yes	–
Who-Has	–	Yes
I-Have	Yes	–

Use the 681 terminal block to connect a shielded twisted pair wire from the BACnet RS485 connection point. Wire the A, B & G conductors from the BACnet point to the 681 A, B & Ref terminals.

And should not be connected to the ground screws in the 681.

STATUS FLAG

In Alarm Flag| F
Fault Flag| F
Overridden Flag| F
Out of Service Flag| F/T

RELIABILITY

No-Fault| 0
No Sensor| 1
Open Loop| 4
Shorted Loop| 5

BACnet Analog Parameters

Analog Input Object = AI
Analog Value Object = AV
Read = R
Read/Write = R/W

OBJECT ID| NAME| DATA
TYPE| READ/
WRITE| STATUS
FLAG| EVENT
STATE| RELIABILITY| OUT OF
SERVICE| UNITS| RANGE/
VALUE
---|---|---|---|---|---|---|---|---|---
Analog Input Objects
1| Outdoor Air
Temperature| AI| R| FFF(F/T)| Normal| 0, 1, 4, 5| False or True| °F (64)| -76 to 266°F
2| Slab

Temperature

| AI| R| FFF(F/T)| Normal| 0, 1| False or True| °F (64)| –
3| Slab Target

Temperature

| AI| R| FFF(F/T)| Normal| 0| False or True| °F (64)| –
4| Error Code| AI| R| FFF(F/T)| Normal| 0| False or True| No Units(95)| See Error Codes list
Analog Value Objects
1| BAS
Outdoor air temperature| AV| R/W| FFF(F/T)| Normal| –| False or True| °F (64)| -76 to 266°F
2| Melt Setpoint| AV| R/W| FFF(F/T)| Normal| –| False or true| °F (64)| 32 to 95°F
3| Snow/Ice
Sensitivity| AV| R/W| FFF(F/T)| Normal| –| –| No Units

(95)

| 0 = Auto, 1 = Min,
2 = -2, 3 = -1, 4 = Mid, 5 = +1, 6 = +2, 7 = Max
4| Warm WeatherShut Down| AV| R/W| FFF(F/T)| Normal| –| False or True| °F (64)| 32 to 95°F
5| Cold WeatherCut Off| AV| R/W| FFF(F/T)| Normal| –| False or True| °F (64)| -30 to 50°F

BACnet Binary Parameters
Binary Input Object = BI
Binary Value Object = BV
Read = R
Write = W

6| NAME| DATATYPE| READ /

WRITE

| STATUS

FLAG

| EVENT

STATE

| OUT OF

SERVICE

| PRESENT VALUE
---|---|---|---|---|---|---|---
Binary Value Objects
1| Snow Detected| BI| R/W| FFF/(F/T)| Normal| False or True| 0 = False
1 = True
2| Cold Weather Cut Off| BI| R/W| FFF(F/T)| Normal| False or True| 0 = False
1 = True
3| Melt Pending Detected| BI| R/W| FFF(F/T)| Normal| False or True| 0 = False
1 = True
4| Wet Detected| BI| R/W| FFF(F/T)| Normal| False or True| 0 = False
1 = True
5| Sensor Mode| BI| R/W| FFF(F/T)| Normal| False or True| 0 = False
1 = True
6| Melt Pending Detected| BI| R/W| FFF(F/T)| Normal| False or True| 0 = 090 Sensor Configured
1 = 095 Sensor Configured

OBJECT ID| NAME| DATATYPE| READ /
WRITE| STATUS
FLAG| EVENT
STATE| OUT OF
SERVICE| PRESENT VALUE
---|---|---|---|---|---|---|---
Binary Value Objects
1| Outdoor Sensor Enable| BV| R/W| FFF(F/T)| Normal| False or True| 0 = Interface measures outdoor
1 = BAS sends outdoor temperature
2| Warm Weather Shutdown Type| BV| R/W| FFF(F/T)| Normal| False or True| 0 = Auto, 1 = Setting
3| Cold Weather Cut
Off Type| BV| R/W| FFF(F/T)| Normal| False or True| 0 = Auto, 1 = Setting
4| Reset Snow Detection Request| BV| R/W| FFF(F/T)| Normal| False or True| 0 = Do nothing,
1 = Reset Snow
Detection

Refer to the Installation & Operation Manual 681_D for additional information.

BACnet MSTP Troubleshooting

If there is no communication, check the following:

Check that the polarity on the BACnet MSTP A & B terminals is correct.
Check that the BACnet MSTP Ref terminal is securely connected.
Check that the baud rate is the same on both devices.

BACnet MSTP Specification

Communication Protocol	MSTP over RS-485
Physical Layer	TIA-485 two-wire plus signal ground
Baud Rate	9600, 19200, 38400, 57600, 76800, 115200 (default: 76800 bps)
Recommended Cable	18 AWG Shielded Twisted pair (STP)
Maximum Cable Length	9600 bps: 1200 meters (4000 feet) 19200 bps: 1200 meters

(4000 feet) 38400 bps: 1200 meters (4000 feet) 57600 bps: 1200 meters (4000 feet) 76800 bps: 1200 meters (4000 feet) 115200 bps: 1000 meters (3280 feet)
Parity| Even (1 stop bit)
Addressing| 0 to 127 (default: 60)

Error Codes

CODE	DESCRIPTION
1	Setpoint Menu Save Error
2	Sensors Menu Save Error
3	BAS Menu Save Error
4	Outdoor Sensor Error
5	Slab Sensor Error
6	Snow Sensor Yellow Wire Error
7	Snow Sensor Blue Wire Error
8	Snow Sensor Brown Wire Error
9	Snow Sensor Error
10	Snow/Ice Sensor