Elk Power Down Rule


Active Member
I want to use ELK to turn an output on/off in case the electric disruption. So turn output 100 on if the main power to the house ie power to elk is cutoff and turn the output off when the electricity is restored.

1. is it possible?
2. I guess in that case I should not have the elk connected to a UPS as that will only happen when the UPS battery runs out.

Looking forward to suggestions.



Active Member
In short, yes it's possible and yes, the M1's transformer will need to NOT be plugged into a UPS.

However, someone else will need to advise on the best approach.

I get email notifications during power outages at installations using a WHENEVER AC FAILURE TROUBLE IS DETECTED rule to trigger an email via the XEP. There's also a WHENEVER AC FAIL RESTORE OCCURS.

Depending on what you want to control, you'll need to know how sensitive this will be. How long after AC goes out before this is triggered. How long AC stays out, etc.

Hopefully someone can supply more details on this, which weren't an issue for me, but may be for you.


Senior Member
What are you going to switch or turn on/off when the AC power is out? Why couldn't you leave the M1 plugged into a UPS and use one of the unprotected UPS AC outputs to power a 110 volt relay that would turn off when the power goes off and turn on when the power goes back on?