Monitor main power feed


#1

I have a generator hookup on my house that I can plug a portable generator into. The switchover process is manual,using a lockout in the main panel. I want to get a notification when the main power feed is re-energized at the meter.

I would prefer not to have to install anything into the box that physically connects to the main feed. Is there anything out there that can detect by proximity if there is power in the lines and send a notification to the HE? Or, any ideas on rigging something that uses a hacked up proximity electrical tester?


#2

I'm guessing you mains comes into your Main breaker. The switchover in next wired so the panel is fed from the street or you generator. Is this correct?

If this is the case and your wiring is like mine, my wiring from the street is completely covered by metal conduit. I don't see the chance to test by proximity.

Ideally, you would have a small sub panel off the switchover that remains on the street feed.

Does your power company send out a message when the power is restored? If so that might help.

I have a "way out" idea. If you have a neighbor close enough to connect via WiFi (and they let you plug in a NodeMCU board). You could use ST-Anything to send out a beacon to your Hubitat Hub when power is restored.


#3

Main power goes into a meter, then runs 30 feet to the main panel. The generator is backfed through a breaker in the main panel. So, to switchover, you have to shut off the main, slide a metal plate up, and then turn on the breaker for the generator. Sounds sketchy, but it meets code without having a dedicated MTS or ATS.


#4

I've seen them. Thought the same.

I've been thinking of a solution to the same issue for some time with no good solution.

When setup up like this, there is no current on the mains when the power comes back on. So non contact current sensor will not work.
A proximity sensor mounted inside the box would be an issue trying to hack it and figuring out how to power it from the mains.


#5

Why don't you use two current transducers, one for each leg (assuming your feed is single phase) connected to dry contact z-wave sensors. The current transducers are not directly wired to the main feed. They even make split core transducers so you won't even have to disconnect each main leg while installing the transducers.

Then setup a rule that notifies you when both sensors are triggered.


#6

When the mains come back on, there will be no current flow until the breaker is turned back on. Those proximity testers would work though.

I will have to research how these work, I think I have a spare one.


#7

In "normal" operation the proximity sensors work because of the capacities coupling from a wire to your body to the ground.

So perhaps a small metal disk with some safety insulation (tape) on a plastic bracket near one of the mains legs (before the breaker) could be used with some sort of low voltage measurement to do what you are looking for.

I think of this idea as a theoretical exercise. I would not recommend this and I would not do it myself.