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Rockwell Automation 1771-IR , D17716.5.76 RTD INPUT MODULE User Manual

Page 36

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Module Calibration

Chapter 7

7Ć3

Table 7.A

Write Block Transfer Word 15

Word Bit 17 16 15 14 13 12 11 10 07 06 05 04 03

02

01

00

Inhibit Calibration on Channel

Requested Auto-Calibration

Word 15

Set

these

bits to 0

6

5

4

3

2

1

Set these bits to 0

Requested

Save

Values

Requested

Gain Cal.

Requested

Offset Cal.

NOTE: Normally, all channels are calibrated simultaneously (bits 10–15 of
word 15 are octal 0). To disable calibration on any channel, set (1) the
corresponding bit 10 through 15 of word 15.

4. Queue block transfer reads (BTRs) to monitor for offset calibration

complete and any channels which may have not calibrated successfully.
Refer to Table 7.B.

Table 7.B

Read Block Transfer Word 9

Word

Bit

17 16 15 14 13 12 11 10

07

06

05 04 03

02

01

00

Uncalibrated Channels

Auto-Calibration Status

Word 9

Not

used

6

5

4

3

2

1

Cal.

Fault

EEPROM

Fault

Not used

Save to

EEPROM

Complete

Gain Cal.

Complete

Offset Cal.

Complete

5. Proceed to gain calibration below.

Gain Calibration

Calibrating gain requires that you apply 402.00 ohms across each input channel.

Normally all inputs are calibrated together. To calibrate the gain of an input,
proceed as follows:

1. Connect 402.00 ohm resistors across each input channel as shown in

Figure 7.2.