New construction with a Koehler full house generator and Koehler transfer switch. All this work done by a licensed electrician. This is a seasonal home and so my ability to monitor is through the Koehler app. When I lose power I also obviously lose my broadband connection so I know - or assume- that power has been lost.

I recently lost connection with the generator and I had to travel to the house I found that all the breakers Han been tripped. The research that I’ve done that the arc fault breakers (which are required by code) are finicky and they have sometime tripped when power returned but it seems weird to me that even the 30 amp dryer breaker tripped.

My concern is that even though power company power and gen power is back but since all the breakers have tripped power to the house is not on so no heat or refrigerator power which defeats the purpose of backup power Has anyone seen this before?

My first thought is to contact the power company to see what power is being delivered to the house. When I test the system by switching between gen an Poco everything works fine. Would a whole house surge protector (like Siemens or Eaton) help with this?

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    What make and model are the breakers and breaker panel in question? Commented Mar 3, 2020 at 12:40
  • Hello, and welcome to Home Improvement. Unfortunately, we'll need more info before we have any chance of helping you. Please take our tour so you'll know how best to participate here. Commented Mar 3, 2020 at 13:09
  • I have not heard of all breakers tripping as the case of a dryer that is not ? An AFCI. if the dryer was not running at the time of the drop out it should not have been affected at all. With a whole house transfer switch it should not matter either as switching from utility to generator is a mechanical process. Some times when power is lost there are 3 bumps before the re-close unit stays open this bump is enough to trip AFCI’s, depending on the control for the transfer switch this can also create electrical noise that will trip some AFCI’s. Photos of panel switch may help
    – Ed Beal
    Commented Mar 3, 2020 at 15:14
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    What's your model of transfer switch? Commented Mar 3, 2020 at 15:45
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    @HikeOnPast read OP further, the router loses power because its circuit breaker trips. The breaker trips because something about the gen changeover is perturbing the AFCI breaker. I am hoping we can learn more from OP about the setup, i fear it may not be answerable as it is. Commented Mar 4, 2020 at 14:43

1 Answer 1


Safety systems don't want safety systems

Goofus McGee got a job as a mechanic at a big warehouse. $100 million of stuff. In the past Goofus has seen large engines get destroyed because somebody didn't check oil level, so Goofus likes to fit low-oil shutoffs. While making the rounds, Goofus discovers that the fire pump diesel does not have any low-oil-level trip on it. So Goofus fits one on there.

The next day, an employee throws a cigerette into a trash can. No big deal; it's a 1-sprinkler-head fire. Sure enough, the sprinkler opens, the fire pump diesel spins up, and promptly shuts down on a low-oil trip. The 1-sprinkler fire becomes 2-sprinkler then 3 then 10, then the whole warehouse is engaged. Total loss. Goofus says "But hey, I saved a $100,000 diesel engine!"

In fact, you do not put low oil, low water, anything like that on a fire pump. For good reason; you want the engine to destroy itself putting out the fire. Engines are cheap.

So here you are, with AFCIs "protecting" your refrigerator (food safety) and your furnace (freeze/flood safety). And no doubt your radon system and fire alarm. Peachy.

This is a plain case of Goofus McGee legislating safety systems without slowing down to care what it is. We often discuss that refrigerators should not have GFCI, they don't need it and they tend to trip it. AFCI protects wires in walls (and to a far lesser extent line cords, but only where often jostled); I'll argue steel conduit is just as good for a fridge, fire alarm, radon, furnace, etc.

Unfortunately Internet routers tend to be a suitable case for AFCI, since they are so frequently wired up in a rat's nest of power strips and splitters. However again, installed properly, I don't see a problem.

The breakers are tripping because of an Arc Fault

Whatever knocked out your power probably caused the arc fault. Tree falling on wires, or what have you. An arc fault is that kind of thing, and it makes a familiar crackly-snap sound on the wire*, and that's what the AFCI is listening for.

What may be throwing you for a loop is that other FCI device only trips on things that happen on its LOAD side; it cares not about ground faults happening on its LINE side. AFCI is a completely different animal, and it is listening on the LOAD side of the device. However, electrical "sounds" transmit right through (that being hard to avoid) and so the AFCI often hears stuff occurring on its LINE side.

I imagine whatever rended the wires off the poles was a heck of a wallop, so the AFCI breakers would have trouble not hearing that.

You could try putting a whole house surge suppressor, but its job is to suppress surges; the sound of a make-break arcing may have surge components, but it's mostly instantaneous brownouts. Your surge suppressor isn't going to carry your power supply across that.

* Sound is jiggling air, so that sounds wrong. But a "sound on a wire" is electrons jiggling in the wire, in exactly the same motions, frequency and proportion. In fact there's a simple interface to take "jiggling electrons" to "jiggling air": It's called a speaker, and it is that simple. Put 60Hz AC on the wire, get 60Hz audible hum in the air. The air movement and electron movement are in syncopation, and fourier analysis will apply identically to both. So it's not out of line to say you can "hear" spikes.

There's another option for low power appliances

In short: why are you running your generator if you aren't even there?

The simple, cheap solution is a small, always-on DC battery system such as in an old-style off-grid solar home. Most internet router equipment is in fact 12 volts DC, and will cheerfully run off a common small 12V system. Add a battery charger both from the mains-only panel and the generator-only panel (or better: a couple of vertically mounted, south-facing solar panels), and your Internet will be solid as a rock.

It would be nice to graft a refrigerator onto such a system, but the fridge takes 1KWH per day; 1 KWH is a car battery sized thing. So such a setup would be more ambitious, maybe 8 golf cart batteries and 1000W of solar panel for an all-solar setup with no gen.

If you have the gen, that's fine; spin it up, recharge the batteries / warm up home, then shut it down.

What usually puts "getting rid of the generator" out of reach for conventionally built snow-belt homes is the air handler needed for the conventional furnace. They alway use either a huge blower, or a water pump, to circulate heat from the furnace to the rooms. This simply takes too much power; the system would need to be fairly large, e.g. a Tesla PowerWall.

Now in the sunbelt we have a wonderful creature called an Empire furnace. It works on convection and performs normally with the power out, relying on a passive wall thermostat. It can also play with smart 'stats like the Nest (while failing over to a mechanical 'stat when power fails). It mounts in a floor or wall, and can heat both sides of the wall, with 50,000 BTU. The units are in the $800 neighborhood. They are just the ticket as a fallback heater to keep a house from freezing. But they are almost unheard of in the snowbelt because, you know, conventional. But they could be part of a power-loss strategy, especially for an unattended home.

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