8
SignalFire Telemetry
Rev 1.6
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 Thermocouple data is sent to the Gateway:
Register
Number
Register Address
(offset)
Register Type
Description
41001
1000
16bit INT
Thermocouple Type (1=J, 2=K)
41002
1001
16bit INT
Thermocouple Temperature (0.1 °C)
41003
1002
16bit INT
Internal Reference Temperature (0.1 °C)
41004
1003
16bit INT
Fault
–
TC Interface board not detected
41005
1004
16bit INT
Fault - Thermocouple shorted to Ground
41006
1005
16bit INT
Fault - Thermocouple is open (not connected)
41007
1006
32bit FLOAT
Thermocouple Temperature degC (Float, High Word)
41008
1007
32bit FLOAT
Thermocouple Temperature degC (Float, Low Word)
41009
1008
16bit INT
Thermocouple Temperature (0.1 °F)
41010
1009
16bit INT
Internal Reference Temperature (0.1 °F)
41011
1010
32bit FLOAT
Thermocouple Temperature degF (Float, High Word)
41012
1011
32bit FLOAT
Thermocouple Temperature degF (Float, Low Word)
In addition to the registers read from the thermocouple board, the Sentinel will send system information in 16-
bit registers listed in the table on the next page. This data is accessible at the same Slave ID as the connected
Modbus device.
If any of the three system faults are detected all temperature values will fail high. The 16bit integer registers will
fail to 32768 and the float registers will fail to +infinity.
