Thermocouple/Mv Input Module (1794-It8) Write; Word/Bit Descriptions For The 1794-It8 Thermocouple/Mv; Input Module - Allen-Bradley 1794-IT8 User Manual

Writing Configuration to and Reading Status from your Module with a Remote I/O Adapter
Decimal Bit 15 14 13
Octal Bit 17 16 15
9
10 0 0
Dec. Bit 15 14
Octal Bit 17 16
Write Word 0
1 Thermocouple 3 Type
2 Thermocouple 7 Type
Where: FDF = fixed digital filter bit
Decimal Bit
Word
(Octal Bit)
Read Word 0 00–15 (00–17)
Read Word 1 00–15 (00–17)
Read Word 2 00–15 (00–17)
Read Word 3 00–15 (00–17)
Read Word 4 00–15 (00–17)
Read Word 5 00–15 (00–17)
Read Word 6 00–15 (00–17)
Read Word 7 00–15 (00–17)
Read Word 8 00–15 (00–17)
00–07 (00–07)
Read Word 9
08–15 (10–17)
Read Word 10 00 (00)
01 (01)
02 (02)
03 (03)
04–06 (04–06)
07 (07)
08 (10)
09 (11)
10 (12)
11–15 (13–17)
12 11 10 09
14 13 12 11
Overrange Bits
Bad Cal
0 0 0
Cal Done

Thermocouple/mV Input Module (1794-IT8) Write

13 12 11 10 09
15 14 13 12 11
8-Bit Calibration Mask
Thermocouple 2 Type
Thermocouple 6 Type

Word/Bit Descriptions for the 1794-IT8 Thermocouple/mV

Input Module

Reserved
Channel 0 Input data
Channel 1 Input data
Channel 2 Input data
Channel 3 Input data
Channel 4 Input data
Channel 5 Input data
Channel 6 Input data
Channel 7 Input data
Underrange bits – these bits are set if the input signal is below the input channel's minimum range.
Overrange bits – these bits are set if 1), the input signal is above the input channel's maximum range,
or 2), an open detector is detected.
Cold Junction sensor underrange bit. – this bit is set if the cold junction temperature is below 0
Cold Junction sensor overrange bit. – this bit is set if the cold junction temperature is above 70
Bad Structure – this bit is set if an invalid thermocouple type is selected.
Powerup bit – this bit is set (1) until configuration data is received by the module.
Critical Error bits – If these bits are anything other than all zeroes, return the module to the factory for
repair
Unused – set to 0
Calibration Range bit – set to 1 if a reference signal is out of range during calibration
Calibration Done bit – set to 1 after an initiated calibration cycle is complete.
Calibration Bad bit – set to 1 if the channel has not had a valid calibration.
Unused – set to 0
08 07 06 05
10 07 06 05
Cal
0 Diagnostic Status
Range
08 07 06 05
10 07 06 05
Cal Cal hi
Filter Cutoff
Clk Cal lo
Thermocouple 1 Type
Thermocouple 5 Type
Description
04 03 02 01
04 03 02 01
Underrange Bits
Pwr Bad CJC
Up Structure over
04 03 02 01
04 03 02 01
FDF Data Type
Thermocouple 0 Type
Thermocouple 4 Type
o
C.
o
C.
Publication 1794-6.5.7 – April 1997
4–5
00
00
CJC
Under
00
00