Backup Generators

Anyone have any experience with Backup generators and Insteon?

A use case I am exploring.

A whole house backup generator kicks in automatically during power failure and 'brown outs'. Need to turn off all non-essential equipment when the generator kicks in. I am assuming here that the non essential equipment is capable of being turned on/off via an Insteon signal.

Questions I have:
1) Will the Mac running Indigo and the connected PLM continue to run at the point of power transfer from utility to backup generator.

2) What is the best way to signal to Indigo that the generator has kicked in.

Any thoughts?

1) Will the Mac running Indigo and the connected PLM continue to run at the point of power transfer from utility to backup generator.

I'd personally put the Mac on a UPS and then attach a FilterLinc or something similar to it (as UPSes are notorious for putting noise on the power line). Even a very brief drop in power might knock your Mac out otherwise.

The PLM shouldn't be attached to the UPS, obviously, but it doesn't really need to (unless Indigo sees it disconnect and freaks).

2) What is the best way to signal to Indigo that the generator has kicked in.

Is there an LED or something that lights up when the generator turns on? You could wire in a TriggerLinc there with minimal damage to the generator, minimal complexity, and quite good reliability. TriggerLincs are among the least expensive Insteon devices, too...

Wiser heads probably have wiser ideas, though.

Any thoughts?

If you don't have any Insteon devices installed yet, I'd grab a couple of LampLincs or something similar and see how well they run on generator power. I imagine the power line being very noisy in such a situation. Every Insteon device I know of reverts to its previous state after a power failure, so they'd all have to be explicitly signaled off, so a noisy line would be very bad news.

Because Insteon works by synchronizing commands to the AC power's zero crossings, you must have a high quality generator in order for Insteon communications to work. I am using a 20KW briggs and stratton generator and have looked at its sine wave output on a scope and it is not bad, but not as good as what comes from the utility. Insteon works OK when the generator is on but I do see intermittent issues like the dimming level not ramping smoothly (it blinks a few times, briefly to full brightness while ramping).

You should start by using a clamp-on ammeter to measure your actual household load for various appliances and lighting. I see you are in New Mexico so the biggest question is do you expect to use your air conditioner - because everything else is going to be very small compared to that, and your AC is going to dictate the size of the gen.

Any reasonably sophisticated transfer switch will include relay contact outputs that open when the generator is overloaded. Ideally you should hard-wire your low voltage thermostat wiring for the AC through those terminals. That's really what they're for.

Insteon (eg IOLinc) might work but I think you're asking for trouble there because the times when thee signals need to be sent will be during periods where the power maybe unstable due to startup, shutdown, or overload circumstances. It's definitely best to hard-wire.

Thanks for the great input.

The hard wire option to the transfer switch is definitely a good idea for overload condition. In the use case though I need to shut down high load appliances (HVAC) as I know the generator will not be able to service that load.

Agree with not sending signals during periods of power instability.

Good idea to put the UPS on the Mac.

Talked to an electrician friend who recommended putting a 'latch relay' to open the circuit during power failure. When power is restored back to the utility and stable for some time (15 minutes) send an insteon signal to the 'latch relay' to close the circuit.

So the senario for the use case so far looks like this:

Utility Power goes out >>

Latch Relay opens circuit, Mac power down, backup generator starts up>>

Backup Generator is up, Mac powers up (how does it know that it is running on backup power?) >>

Utility Power comes Back, (Does the Mac stay up during the transfer?)>>

Mac creates a trigger/timer to check if Utility Power has been stable for some time. (Need to think through the programming logic here)>>

If Utility power has been stable send a 'restore' signal to the latch relay.(I still have to figure out how to signal the latch relay.)

Will post when I know more.

The reason to have a UPS connected to the Mac, is it wouldn't go down. It will run on built-in batteries during transfer time (starting genset, or back to mains).
One thing, if you don't put the interface on UPS, then Indigo will know when the power is gone (it can't see the interface anymore). The problem is to sense the Mains coming back. So a triggerLink is still what you need....

This is the learning so far in trying to solve for the following use case:

A whole house backup generator kicks in automatically during power failure and
'brown outs'. Need to turn off all non-essential equipment when the generator
kicks in.


So the senario for the use case so far looks like this:

Utility Power goes out >>

Four Pole ice cube Relay opens circuit to non essential equipment(see diagram below), Mac powers down,
backup generator starts up>>


Backup Generator is up, Mac powers up and Indigo pings an IP device on the utility side only
to determine when utility power is up >>

Utility Power comes Back>>

Indigo checks if Utility Power has been stable for some 30 minutes.

If Utility power has been stable Indigo to send a 'restore' signal to the ice cube relay.(I
still have to source a IP to contact closure device.)