ABB GLA131 Series Microportable Analyzers
User Manual
ABB PROPRIETARY INFORMATION
62
contain the same data and are interchangeable to provide the greatest flexibility
for recording data.
The analyzer process variables and their order can be found in the local data file as
a header or as listed in Table 10. These columns of data are mapped directly into
the Modbus holding register starting at 040000. Except for the timestamp (
Epoch
Time
), each process variable occupies two holding registers to represent a
floating-point value. Both registers must be read to properly return the process
variable of interest. Table 10 lists analyzer process variables, registers, and bit
assignments.
Table 10: Analyzer Process Variables
Variable
Register
Data Format
Epoch Time (ms)
040000
Lease Significant Bit (LSB)
040001
040002
040003
Most Significant Bit (MSB)
[CH4]_ppm
040004
LSB
040005
MSB
[CH4]_ppm_sd
040006
LSB
040007
MSB
[CO2]_ppm
040008
LSB
040009
MSB
[CO2]_ppm_sd
040010
LSB
040011
MSB
[H2O]_ppm
040012
LSB
040013
MSB
[H2O]_ppm_sd
040014
LSB
040015
MSB
[CH4]d_ppm
040016
LSB
