Invoking autocalibration, Invoking autocalibration -10 – Rockwell Automation 1746-NR8 SLC 500 RTD/Resistance Input Module User Manual User Manual

Page 82

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Publication 1746-UM003A-EN-P

5-10 Ladder Programming Examples

Invoking Autocalibration

Autocalibration occurs whenever:

power is provided to the module

a change is made to its input type, filter frequency, or excitation current

an operating channel is disabled and re-enabled using its enable bit

the periodic calibration bit is toggled from 1 (disable) to 0 (enable) and back
to 1 (disable)

Referring to the following ladder, you can command your module to perform
an autocalibration cycle by toggling the periodic calibration bit (bit 15).

To maintain system accuracy we recommend that you periodically perform an
autocalibration cycle, for example:

whenever an event occurs that greatly changes the internal temperature of
the control cabinet, such as opening or closing its door

at a convenient time when the system is not making product, such as during
a shift change.

Channel 7
Enable

I:3.15

11

Channel 7
Broken Input

I:3.15

13

Channel 7
Out of Range

I:3.15

14

Channel 7
Calibration
Error

I:3.15

15

Channel 7
Alarm

O:2

7

1746-O*16

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