Performing auto-calibration, Module calibration chapter 7, Offset calibration – Rockwell Automation 1771-IXHR , D17716.5.80 HIGH RESOL.THERMOCOUPLE User Manual

Page 36

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Module Calibration

Chapter 7

7Ć2

Calibration of the module consists of applying 0.000mV across each input
channel for offset calibration, and +100.000mV across each input channel for
gain correction.

Offset Calibration

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

1. Apply power to the module.

2. Connect shorting links, or apply 0.000mV across each input channel on

the 1771–WI field wiring arm as shown in Figure 7.1.

Figure 7.1

Shorting Inputs for Offset Calibration

1

Do not

use

18 Input 1 (+ lead)

17 Input 1 (- lead)
16 Input 2 (+ lead)
15 Input 2 (- lead)

14 Input 3 (+ lead)

13 Input 3 (- lead)
12 Input 4 (+ lead)
11 Input 4 (- lead)
10 Not Used

9 Not used

8 Input 5 (+ lead)
7 Input 5 (- lead)

6 Input 6 (+ lead)

5 Input 6 (- lead)
4 Input 7 (+ lead)
3 Input 7 (- lead)
2 Input 8 (+ lead)
1 Input 8 (- lead)

Terminal Identification

Terminal Function

Wiring Arm

Cat. No. 1771-WI

18

17

16

1

15

14
13

12

11
10

9
8

7

6
5
4
3

2

Repeat for each channel

Apply

0.000mV

Short each input,

or apply 0.000mV

across each input

channel.

Shorting link.

10530-I

3. After the connections stabilize (about 10 seconds), request the offset

calibration by setting bit 00 in block transfer write word 28 and sending a
block transfer write (BTW) to the module. Refer to Table 7.A.

When the BTW is sent, all channels are calibrated to 0.000mV.

Performing Auto-calibration

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