Rockwell Automation 1794-IRT8XT FLEX I/O Thermocouple/RTD /Millivolt Input Module User Manual User Manual
Page 49
Publication 1794-6.5.12 - September 2011
Read and Write Configuration Maps for the FLEX I/O Module 37
1
0
0
1
T -270…400 °C (-454…752 °F)
1010…1111 not used
Bits 12…13
(14…15)
Sensor Mode Select bits
Bit
13 12 Sensor mode select for channels 4…7
Thermocouple
0
0
External compensation
– uses cold junction sensors. Both CJC sensors must be
used when external compensation is selected.
0
1
Internal compensation
– uses the user selected Reference Junction.
1
0
No compensation. Data is referenced to 0 °C (32 °F).
1
1
Differential measurement between 2 channels.
RTD
0
0
2-wire RTD no compensation
0
1
2-wire RTD with user selected offset
1
0
3-wire RTD
1
1
4-wire RTD
Bits 14…15
(16…17)
Input Type Select
Bit
15 14 Input type selection for channels 4…7
0
0
Thermocouple
0
1
RTD
1
0
Not used
1
1
Not used
Write Word 2
00…15
(00…17)
RTD offset select bits
– used when input type is set to RTD and sensor mode select is set to 2-wire
with user selected RTD offset. Allows you to set the type of RTD loop resistance compensation used
for all RTDs or one of three fixed values for all channels.
NOTE:
Not applicable to 10
Ω
copper RTD.
Bit
01 00 RTD Offset Select Bits – channel 0
03 02 RTD Offset Select Bits – channel 1
05 04 RTD Offset Select Bits – channel 2
07 06 RTD Offset Select Bits – channel 3
09 08 RTD Offset Select Bits – channel 4
11 10 RTD Offset Select Bits – channel 5
13 12 RTD Offset Select Bits – channel 6
15 14 RTD Offset Select Bits – channel 7
0
0
Use channel loop compensation value stored during calibration procedure for 2-wire
RTD (default = 0
Ω
)
0
1
5
Ω
(total lead resistance)
1
0
10
Ω
(total lead resistance)
1
1
15
Ω
Bit/Word Descriptions for Block Transfer Write Words
Word
Dec. Bits
(Octal Bits)
Description