ECN Forum Forums General Topics of the Trade General Discussion Area Designing for Power Outages

As I was setting up my generator this morning, one thing became apparent: I had no easy way to power my alarm, cameras, phone, and computers, short of putting the entire house on the generator.

So, I wonder .... is it a good idea to have a separate circuit, hopping from room to room, providing power to receptacles dedicated to these uses? One could even make this a circuit separate from the usual house wiring, powered only when the generator is in use. Power failure? Just move the plugs.

I almost think I have seen this arrangement in medical facilities- an "emergency" receptacle right next to the 'ordinary' receptacle.

I rather like this arrangement, as it makes the generator network completely separate from the utility-powered network ... no need for transfer switches, no chance of backfeed issues. While the NEC seems to assume transfer switching, I don't think a parallel network is forbidden.

For "down the road" applications, perhaps a dedicated small panel feeding all of the generator powered circuits could be installed. If you decide to install a transfer switch later, some of the wiring is already installed. You would just have to move other dedicated circuits later. It would allow you to run the 240 V output of the generator and give you more power available for the larger loads during an extended outage.

Reno:

An inlet, backfed cb, and an interlock kit gets the gen power into your panel. You have to select the branch cbs you want to power up, Works fine for me, and a lot of others, and it's legal.

Reno:

Yes, there are multiple sources in some medical facilities. The "emergency", red HG duplex, and matching plate are from the gen.

I have a back feed inlet and an interlock kit here. I am really not that prepared tho. I do have a good panel directory but I have not really gone through and mapped the breakers I would want to have on and the normal load on them. Best case would actually be a load rating on each "emergency" breaker and a list of which will work with the others.

Does anyone see a need for surge suppression on generator-fed circuits? Just how reliable is their voltage regulation (especially as your load varies)?

I doubt surge protection would buy you much on a typical portable generator. Your biggest problem is usually sags.

If I ever do decide to test my setup and I think of it, I will hook up my Dranitz and see what I have.

When the day comes to reno the basement I plan on installing a standby gen with an automatic transfer switch. How big of a standby gen I plan on using is the debate.


Reno, are you mostly concerned with surge suppression for ccts powering electronics? I think I would have a UPS ahead of the generator to deal with that concern.

Potseal, as I see it, the joker in the sizing decision is the starting current required for motors. When your overall load is as small as mine - or when, in my case, all I'm powering right now is one motor - that starting current matters.

Now, my generator, even when bought at a bargain price, cost me more than many similar capacity generators that I see in some retail outlets? Why pay more? Well, the biggest differences are in the noise made and the reliability of the voltage regulation.

There's my concern about voltage spikes: the voltage regulation of the generator as loads change. I would hate for a high-voltage spike when the furnace motor stops to cause harm to any electronics that might be on line.

Yes, a UPS would help; I had forgotten about that. That might be a solution.

Greg, I'd love to see what actual measurements show.

These days electronics are really not what I worry about. They usually have switch mode power supplies that tolerate anything from 100v to 250 or so. It makes them easier to sell around the planet.