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Default configuration – Rockwell Automation 1771-IXHR INSTL INSTR HI RES TC/MV INPUT User Manual

Page 8

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High Resolution Thermocouple/Millivolt Input Module

8

Publication 1771-5.66 – October 1998

Use the following table to read data from your input module.

Dec. Bits

15

14

13

12

11

10

09

08

07

06

05

04

03

02

01

00

De

o

Octal Bits

17

16

15

14

13

12

11

10

07

06

05

04

03

02

01

00

Description

Word 1

Not used

EE

DCB

HCJ

LCJ

RTS OR

PU

Diagnostics

EEPROM status bit – (EE) calibration values could not be read.

High cold junction temperature bit - (HCJ) set when
the cold junction temperature exceeds 60.0

o

C or 140.0

o

F.

Low cold junction temperature bit - (LCJ) set when the
cold junction temperature is less than 0.0

o

C or 32.0

o

F.

Real time sample fault bit – (RTS) 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.

Power up bit – (PU) set to indicate
that the module is waiting for its first
write block transfer.

Out of range bit – (OR) set if one or
more channel inputs are above or below
the range for which you configured the
module.

Dynamic clamp bit - (DCB) Prevents rapid changes in data due
to data corruption over the opto–isolation barrier as a result of
ESD, radiation bursts, etc.
0 = feature active
1 = feature inhibited

Octal Bits

17

16

15

14

13

12

11

10

07

06

05

04

03

02

01

00

Description

2

Inputs overrange

Inputs underrange

Inputs overrange and underrange for
c annel 1-8

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.
Overrange bit for each channel is set to indicate an input is out of range: bit 08 for
channel 1 thru bit 15 for channel 8. Also set for open channel detection.

channels 1-8

3

Inputs > high alarms

Inputs < low alarms

High and low alarms for
c annel 1-8

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 (BTW word 4, 6, 8, 10, 12, 14, 16, or
18): bit 00 for channel 1 thru bit 07 for channel 8.
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 (BTW word 5, 7, 9, 11, 13, 15, 17,
or 19): bit 08 for channel 1 thru bit 15 for channel 8.

channels 1-8

4, 5, 6, 7, 8,

9, 10, 11

Input for channels 1-8 respectively in 0.1

o

C or 0.1

o

F resolution for temperature and 10

µ

V

or 1

µ

V resolution for millivolts.

Input for channels 1-8

12

Cold junction temperature is provided in 0.1

o

C or 0.1

o

F resolution. The filter time constant

(Tau) for this value is fixed at 6.4 seconds.

Cold Junction Temperature
in

_C or _F

13

Uncalibrated channel bits

CF

EE

Not used

S

G

O

Auto-calibration word

EEPROM fault bit

Save to EEPROM bit

Offset calibration complete bit

Calibration fault bit

Gain calibration complete bit

Default Configuration

If a write block of five words with all zeroes is sent to the module,
default selections will be:

millivolt input

zoom center = 0mV

temperature reported in degrees Celsius

real time sampling (RTS) inhibited

no filtering

no auto-calibration