GE DigitalFlow XGS868i, Programming Manual

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Chapter 1. Programming Site Data
38 DigitalFlow™ XGS868i Programming Manual
1.9.4 Requesting Parameters Using MODBUS
To request specific parameters from the XGS868i via the MODBUS, the control system must enter the appropriate
register number. Only registers 1 through 90 are available for MODBUS communications, while registers 508 through
512 are used by the XGS868i to store the MODBUS parameters. For details, see Table 11 below for a 1-Channel meter
or Table 12 on page 39 for a 2-Channel meter.
Note:
If you request Channel2 or Averaged data from a 1-Channel meter, the values will all be zero.
Table 11: MODBUS Registers for a 1-Channel XGS868i
MODBUS
Reg #
DPR
Hex Addr Description
Scaling
(decimal places) Size in Bytes
1 0
1”
Clear Ch1 Totalizers”
-- 2 (16 bit signed)
2 2 Not Used -- 2 (16 bit signed)
3 4 Velocity 2 4 (2 16-bit int)
5 8 Act Volumetric #Q DIGITS 4 (IEEE 32 bit)
7 C Std Volumetric #Q DIGITS 4 (IEEE 32 bit)
9 10 Fwd Totals #T DIGITS 4 (2 16 bit int)
11 14 Rev Totals #T DIGITS 4 (2 16 bit int)
13 18 #Tot Digits 0 2
14 1A Mass Flow #M DIGITS 4 (IEEE 32 bit)
16 1E Fwd Mass Totals #MT DIGITS 4 (2 16-bit int)
18 22 Rev Mass Totals #MT DIGITS 4 (2 16-bit int)
20 26 #Mass Tot Digits 0 2
21 28 Timer 2 4 (2 16-bit int)
23 2C Error Code 0 2
24 2E Sound Speed 3 4 (2 16-bit int)
26 32 Density 4 4 (2 16-bit int)
28 36 Signal Strength Upstream 1 4 (2 16-bit int)
30 3A Signal Strength Downstream 1 4 (2 16-bit int)
32 3E Temperature 2 4 (2 16-bit int)
34 42 Pressure 3 4 (2 16-bit int)
508 3F6
2
MODBUS baud rate
0 2
509 3F8
3
MODBUS parity
0 2
510 3FA
4
MODBUS stop bits
0 2
511 3FC MODBUS meter addr 0 2
512 3FE RESERVED --- ---