Detcon PI-700 - Manual (Page 32)

Model PI-700
PI-700 Instruction Manual Rev. 2.5 Page 28 of 54
FC REG Content Description R/W Content Definition
Value Meaning Range
03/
06
40012 Special #2 R/W Function dependent on value of
40006 (See Special Register
Table 4)
03 40013 Special #3 R Function dependent on value of
40006 (See Special Register
Table 4)
03/
06
40014 Special #4 R/W Function defendant on value of
40006 (See Special Register
Table 4)
03
06
40015
40015
Calibration Status
Calibration Enable
R
W
0x0000
0x0001
0x0002
0x0003
0x0004
0x0001
0x0002
0x0008
0x0009
0x000A
0x000B Idle
Zero Calibration Started
Span Calibration Started
Span Set
Span Calibration Unsuccessful
Set Zero
Set Span
Signal simulation mode
Set FP Bridge Voltage
Set TP Heater Power
Set IR Gain
03 40016 Read Text 1, first char in
L
R Two Char of Gas/Units String 6
03 40017 Read Text 2 R Two Char of Gas/Units String 6
03 40018 Read Text 3 R Two Char of Gas/Units String 6
03 40019 Read Text 4 R Two Char of Gas/Units String 6
03 40020 Read Text 5, last char in
H
R Two Char of Gas/Units String 6
03 40021 Text null terminator in L R Two Char of Gas/Units String 6
1 Integer ranges from 1 all the way to 10,000.
2 Units are determined by “units” field in the “notation” string
3 Gas Reading times one (x 1) with units in notation string for “Low Range” = 0. Gas Reading times one (x 10) with units in notation string for “Low
Range” = 1. Gas Reading times one (x 100) with units in notation string for “Low Range” = 2.
4 Span Gas must be less than or equal to Detectable Range and is usually about ½ of it.
5 Fault status bits self-reset when fault clears
6 Text in ASCII, in order L byte, H byte, L byte… See field descriptions of notation string.
Gas/Units String
Character # 1 2 3 4 5 6 7 8 9 10 11
Description Units 0x20 Gas Type 0x00
Units – This field is ‘PPM’, ‘PPB’, or ‘_ _ %’ (where ‘ _ ‘ is a space, 0x20).
0x20 – The units filed is terminated with an ASCII space (0x20)
Gas Type – This field contains the gas type of the cell. Any ASCII string is permissible
0x00 – The notation string is terminated with an ASCII null character
Table 4 Modbus™ Special Registers
REG DM (40006 = 1) FP (40006 = 2) IR (40006 = 3) TP (40006 = 4) 1 PI (40006 = 5)
40011 Low Range= 0, 1, 2
0: Range >25 (0 decimal place)
1: Range 10-25 (1 decimal place)
2: Range <10 (2 decimal place) Gas Factor (R/W)
Range = 79 to 565 Gas Factor (R/W)
Range = 20 to 565 Heater Power
(mW) (R/W) Low Range= 0, 1, 2
0: Range >25
1: Range 10-25
2: Range <10
40012 0x8XXX
0x0XXX
0xX000
0xX096
0xX0C8
0xX12C Positive Polarity Cell
Negative Polarity Cell
Bias = 0mV
Bias = 150mV
Bias = 200mV
Bias = 300mV Cal Factor (R/W)
Range = 79 to 565 Active Counts Heater Voltage
(mV) 0x8XXX
0x0XXX
0xX000
0xX096
0xX0C8
0xX12C Positive Polarity
Cell
Negative
Polarity
Cell
Bias = 0mV
Bias = 150mV
Bias = 200mV
Bias = 300mV
40013 Gain Code
(integer between 0 & 15) Bridge Current (mA) Reference Counts Sensor Resistance
(x100 Ω) Gain Code
40014 Raw Counts 0-0xFFFF
(0x8000 = nominal 0) Bridge Voltage (mV)
(Read only) Range Divisor
1,10,100, or 1000 Heater Current
(mA ) Raw Counts
1 Only possible ranges are 20, 50, 100, 200. Modbus register 40001 will contain either 20, 50, 100, or 200, range divisor is not necessary.