9
SignalFire Telemetry
Rev 1.3
Remote Modbus Register Mapping
The Sentinel Node sends data to a SignalFire Telemetry Modbus Gateway. The data that is sent to
the gateway is available at the gateway in registers where it can then be read by a Modbus RTU.
The following data is sent to the Gateway:
Register
Number
Register Address
(offset)
Description
41001
1000
RTD Sensor Type (2=2/4wire, 3=3wire)
41002
1001
RTD Sensor Resistance at 0°C (
Ω
) (100, 1000, etc)
41003
1002
RTD Temperature (0.1 °C)
41004
1003
Fault
–
RTD Interface board not detected
41005
1004
Fault
–
RTD Low Threshold
41006
1005
Fault
–
RTD High Threshold
41007
1006
Fault
–
RTD Over/Under Voltage
41008-41009
1007-1008
RTD Temperature °C (32-bit float)
41010
1009
RTD Temperature (0.1 °F)
41011-41012
1010-1011
RTD Temperature °F (32-bit float)
49987
9986 or 65523
Status (0=no errors, 1=low battery, 2=failed sensor read, 3=low
battery and failed sensor read)
49988
9987 or 65524
Major revision number for the mainboard
49989
9988 or 65525
Minor revision number for the mainboard
49990
9989 or 65526
Major revision number for the radio
49991
9990 or 65527
Minor revision number for the radio
49992
9991 or 65528
High 16 bits of SFTS node address
49993
9992 or 65529
Low 16 bits of SFTS node address (the radio ID)
49994
9993 or 65530
Slave ID readback
49995
9994 or 65531
Received signal strength of last packet from the slave
49996
9995 or 65532
Battery voltage of the Sentinel-RTD, in millivolts
49997
9996 or 65533
Minutes until this slave will time out, unless new data is received
49998
9997 or 65534
Number of registers cached for this slave device
49999
9998 or 65535
Remote device type. 51 (0x33) for Sentinel RTD
If any of the RTD system faults are detected all RTD register values will fail high. The 16bit integer registers will
fail to 32768 and the float registers will fail to +infinity.
Note: The status registers are only available from the 49987-49999 (9986-9998) address range if the gateway is
running firmware 7.52 or higher.
