Technical Manual
XNX Universal Transmitter
Appendix B - Modbus Protocol
185
B.2 Modbus Registers
Modbus Holding
Register Address
Datatype Variable Name Description
40001 Int16 ID MSB always 0x24 to facilitate automatic identiî§cation. LSB repeat of Modbus address.
40002 Int16 ID Identical to 40001
40003 to 40004 Float32 fCurrentConc
The reported gas concentration in current measurement units. For example, methane at 50% LEL would be reported as 50.0 here.
This concentration is forced to zero during inhibit mode.
40005 int16 iFaultWarnNumber
This is the integer representation of the fault status. If any fault exists this will take a value in the range 1000 to 1999. Otherwise,
if any warning exists, this will take a value in the range 1 to 999. Normally, this has the value zero. For example, if the XNX
temperature is out of range, this will take the value 1103.
40006 int8 iAlmFltLev
This register contains 4 meaningful bits regarding the presence of alarms or faults. The bit assignments are as follows: Bit 0:
AL1
active Bit 1: AL2 active Bit 4: Warning active Bit 6: Fault Active All others: For future expansion