Yes.
I thought about using the dryer receptacle. But it’s on a 30 A circuit, and I wanted it to be on a 50 A circuit. So I installed a 50 A circuit and receptacle.
Yes.
I thought about using the dryer receptacle. But it’s on a 30 A circuit, and I wanted it to be on a 50 A circuit. So I installed a 50 A circuit and receptacle.
How fast does an auto-transfer switch work? Since it’s unlikely that the generator and the mains would happen to be perfectly in phase, I’m imagining that a rapid switchover could cause problems for appliances that don’t like a discontinuous jump in phase angle. Is there a built-in delay to protect these kinds of devices, and/or refrigerators, freezers, and air conditioners whose compressors don’t like restarting after a power interruption that lasts just a few seconds?
Circumstances vary. My greatest concern is losing power during winter, and having pipes burst, but that concern is reducing. I’m pulling out the baseboard heaters which would be the biggest problem, and the rest of the copper plumbing is being replaced with PEX. That means even in very cold weather there will be time to get the generator set up and going. Even without it I could keep the house warm enough to stop pipes from bursting with a propane space heater, and I could also run the oil burner using a 2000watt inverter powered by a car. That’s how I would keep the refrigerator running during summertime power outages. So having a large portable generator and using an interlock adds some convenience to the process, and it will power a lot more than a refrigerator or oil burner.
There is work to do in the event of an outage. I have to go outside to a small metal shed where the generator lives, connect a propane tank to the generator, turn the fuel switch to propane, push a button and hope it starts up just like it has have every single time. Knowing that it’s running I’ll go shut off the main breaker in the main electrical panel, followed by all the breakers in that panel and a sub-panel, plug a humungous extension cord into a receptacle in the back of the house and then into the generator. At that point I can switch on a 50 amp breaker on the main panel to power it up. I’ll switch on the breakers for the necessary circuits one by one after that. An automatic switch doesn’t require any of that effort, but this whole setup cost me only $2,000 two years ago, including the shed. Estimates for a permanent installation ran around $10,000 at the time, and I doubt that covered everything. While a permanent generator will add value to a house it would also increase my taxes. The only permit I needed was to add the outdoor receptacle for the generator, and I only bothered to do that because of other electrical work being done at the time and the inspector might have noticed it.
That’s half the reason. The other half is that, unless the outage has isolated just your house from the rest of the grid, your generator would also be feeding every other house in the “island” created by the outage. There’s a good chance the generator either wouldn’t be able to start spinning due to the sheer load, or would randomly overload when neighbors turn on large loads.
What do generator owners think about the noise issue? My neighbor two doors down has a generator, maybe 100 feet away, and when it’s running the noise in my house is pretty obnoxious. If I had my own generator running right outside the house for hours or days, I would think it would drive me crazy.
Generators can be very quiet. How often they actually are, I don’t know.
Even a loud one is probably an improvement over being without power for an extended time, though.
It can be obnoxious. When we’ve had long power outages in my neighborhood in the past, the sound of the gasoline-powered generators up and down the street is pervasive – especially since those outages tend to happen in the summertime, and with no power for air conditioning, one tends to have every window in the house open, letting in all the sound.
I think the sound of my generator is comparable to my neighbors gas powered lawn mower. Of course lawn mowers don’t run for hours at a time.
There is no way an generator could come on line with out a time delay.
On a single phase ATS (automatic transfer switch) there will be two small relays. Each connected to one of the hots and neutral (ground). If one or both legs goes out the relay will open. That will close a contact starting the generator start routine. When the generator gets up to speed then the contacts from the utility will open. After they are opened the contacts for emergency power will close. Depending on the generator this will take a few seconds up to about 30 seconds. If the generator starts the 1st attempt.
When power is restored, the start run relays will open. on many ATS there will be a time delay of 5 to 10 minutes before the ATS emergency generator contacts will open, and after they are opened the utility contacts will closed. And again some ATS have a cool down time delay before turning off the generator.
And typically don’t run well into the night, either.
The generator doesn’t start up until several seconds after an outage. The switching from utility power to gen backup only takes a second, but you’re already without power when this happens. The generator has to start and warm up before the load gets applied, and this only occurs after power is out from the utility. When utility power comes back the generator will run for a few minutes or so and then switch back to utility power. The switch back to utility power takes about 1-2 seconds or so, so there is another power interruption at that point. Brief, but long enough for equipment to not be affected by phase issues.
I think the sound of my generator is comparable to my neighbors gas powered lawn mower. Of course lawn mowers don’t run for hours at a time.
Whole house NG units are very quiet. You can have a conversation standing next to the running unit.
A number of my neighbours have whole-house natural gas generators. We seem to have fairly frequent power outages that are quiet brief. If the outage is more than about 2-3 minutes, you hear all the generators fire up if the windows are open.
The last time we had an extended outage was the Northeast Blackout of 2003 where we were in the dark for about 10 hours. It’s hard for me to justify a generator for a once-in-a-generation event.
And if you have something that genuinely can’t tolerate even a few minutes of outage, then that whatever-it-is should be on a battery-based uninterruptible power supply. In addition to the generator, because UPSs aren’t good for very long.
What do generator owners think about the noise issue?
It’s an issue for our house, not so much the neighbors who are fairly far away with trees and bushes in between. The generator is just 15 feet away from the back of the log cabin part of the house. Logs do not block sound well. The shed it’s in breaks up a lot of the sound so that helps. I’m planning to put some sections of stockade fence around it for more of a sound break, and possibly I can work out a muffler that may greatly reduce a lot of noise.
And if you have something that genuinely can’t tolerate even a few minutes of outage, then that whatever-it-is should be on a battery-based uninterruptible power supply.
Yep, my network equipment and servers are all on a UPS which should last about 45 minutes but the servers are all set to shutdown after 10 minutes which should give my router 4 hours or so without the rest of the load.
How fast does an auto-transfer switch work?
Depending on the generator this will take a few seconds up to about 30 seconds.
My office building has a whole building emergency generator that runs from utility supplied natural gas. It is supposed to start and be ready for a load withing 30 seconds. Because of that, I have sized my UPS batteries to only need to run for about 10 minutes. In my experience, the generator takes over from the batteries in 10-20 seconds.
Prior to the installation of the large outdoor generator, like you might see behind a hospital, we had a much smaller generator that was inside the building, and could only handle a few key circuits related to climate control of the animal facility. That meant for many years I had a network closet with a V8 engine in it.
It was a Chrysler V8 with (if I remember correctly) red valve covers, a radiator connected to a vent on an exterior wall, and an exhaust stack through the roof. It was extremely loud to be in the same room while it ran. On the wall next to it was the fiber link to the building, network switches, and phone switches.
My experience predates inverter type units, so with that in mind, here’s my experience from 19 years ago. Probably still good data.
There are/were two speeds. 1800 rpm and 3600 rpm. Then there are water cooled and air cooled.
1800 RPM water cooled are the quietest units, while 3600 RPM air cooled are the noisiest.
I live in a rural subdivision, so noise isn’t a factor. In the summer I can sleep fine with the generator running and the AC is on.
The last time we had an extended outage was the Northeast Blackout of 2003 where we were in the dark for about 10 hours. It’s hard for me to justify a generator for a once-in-a-generation event.
There are parts of the country where extended outages are considerably more common. And the power grid in general is getting less reliable due to a variety of factors, most recently loonies sabotaging power substations.
We analyzed power outages from 2022 and the past 20 years to learn which states have suffered the most and what the future of energy looks like in the U.S.
There are parts of the country where extended outages are considerably more common.
No question there is a need for it in many areas where outages are either more frequent or for extended periods. I’m on city water and have natural gas and could easily ride out most blackouts except in the most extreme freezing conditions.