ControlLogix Analog Input Cal LED flashing

Hi,

I have just powered up my ControlLogix PLC with analog input 1756-IF16H.

Two of the module shows an indicator:
-Cal flashing green
-OK steady red

The other AI modules only shows OK steady green.

What do I have to do for the two modules?
In the manual says it has not finished calibration. Should I calibrate it?

Thanks,
Junot

Junot,

I believe that 1756 Analog modules do not retain any knowledge of being in "calibration" mode, and that simply cycling power on the chassis, or removing and re-inserting the module should reset it to normal operation.

Nor can I find any relevant tags in the {location}:{slot}:C tags that might be set to drive it into calibration mode.

I do know that for other modules (e.g. 1756-IF6I and 1756-IF4FXOF2F), cycling power on the chassis clears the flashing CAL led and resumes the module to normal operation.

If the flashing CAL Led persists through a power cycle of the 1756-IF16H module, the I suggest you go into the module properties for each module, choose the "Calibration" tab, Click on "Start Calibration" as if you were going to calibrate it, then click on "Stop" to terminate calibration mode.

If the above doesn't work, try removing the modules from the I/O configuration of the project (offline), and put them back again as new modules. Your project should verify OK, and you can then download the project to the controller. This cleans up the "...:C" tags, which will then be sent to the modules to establish the connection with them.

If none of the above suggestions works, my best guess is the modules are faulty.

If you have access to the knowledgebase, you could try searching for things like "Stuck in CAL mode", "CAL flashing" etc., to see if there is a known anomaly, or you could contact RA Tech Support....