Micro Logix Power fail status

[jeevan.tp]

Dear all,

I would like to hear Some suggestions for Capturing Power fail status and Power resumed status in Micro logic 1400

My requirement is

If power fail occur while PLC is performing certain Operation, I need to Know when the Power fail has occur and when it was resumed with time so i can calculate the duration of power fail

 

[MarkNightingale]

You will have to use a second device.

Once the power goes off to the Micrologix, the code is no longer being scanned, so you won't be able to use the PLC to tell you how long the power has been off.

And whatever it is you choose, whether it be another PLC, or an external timer, you will need to power it from a different supply than the PLC.

Cheers

Mark

 

[janner_10]

A simple/cheap approach: (depending on which Micrologix you have) you could datalog a tag every minute and review where the gap in the data is.

 

[geniusintraining]

And to add to janner_10 with a 'last scan bit' you could set the bit, with a simple counter that indexes once a min, the PLC will run one last scan as the power is lost

The OP is using a 1400 so it should be easy