Bit/word descriptions – Rockwell Automation 1771-IXE/D Thermocouple/Millivolt Input Module User Manual User Manual
Page 38
5–2
Module Status and Input Data
Publication 1771Ć6.5.130 Ć May 1999
The complete bit/word description for the block transfer read from
the module is defined in Table 5.B.
Table 5.B
Bit/Word Description for Thermocouple/Millivolt Input
Module (1771-IXE/D)
Word
Bit
Definition
Word 1
Bit 00
Power-up bit is set to indicate that the module is waiting for its
first write block transfer
Bit 01
Out of range bit is set if one or more channel inputs are above
or below the range for which you configured the module
Bit 02
Real time sample time-out bit is set when the module updates
an input buffer with new data before the processor has read
the previous data. Monitor this bit only if you select real time
sampling.
Bit 03
Not used
Bit 04
Low cold junction temperature bit is set when the cold junction
temperature is less than 0
o
C.
Bit 05
High cold junction temperature bit is set when the cold junction
temperature exceeds 60
o
C.
Bit 06
Not used
Bit 07
EEPROM calibration values could not be read.
Bits 10-17
Polarity bit for each channel is set to indicate negative polarity:
bit 10 for channel 1 thru bit 17 for channel 8. These bits are
used in BCD and signed magnitude data formats.
Word 2
Bits 00-07
Underrange bit for each channel is set to indicate an input is
out of range: bit 00 for channel 1 thru bit 07 for channel 8.
Bits 10-17
Overrange bit for each channel is set to indicate an input is out
of range: bit 10 for channel 1 thru bit 17 for channel 8. Also set
for open channel detection.
Word 3
Bits 00-07
Low alarm bit for each channel is set to indicate the input is
less than the low limit value you entered in the corresponding
low alarm word (word 4, 6, 8, 10, 12, 14, 16, or 18): bit 00 for
channel 1 thru bit 07 for channel 8.
Bits 10-17
High alarm bit for each channel is set to indicate the input has
exceeded the high limit value you entered in the
corresponding high alarm word (word 5, 7, 9, 11, 13, 15, 17, or
19): bit 10 for channel 1 thru bit 17 for channel 8.
Words 4-11
Input for channel 1 through 8 respectively.
Word 12
Cold junction temperature in
o
C.
Word 13
Auto-calibration word.
Bit 00
Offset calibration complete bit
Bit 01
Gain calibration complete bit
Bit/Word Descriptions