I’m looking at purchasing a 7kW propane backup generator – probably Generac carried by local vendor. (waiting on pricing from the Kohler dealer). However, the 7kW model w/ automatic transfer switch only allows 8 circuits; I’m considering the 10kW which allows 10 circuits.
Not being an electrician, can you connect a 10kW to the whole house panel? (during power outage I sure wouldn’t run the Unisaw).
Follow-up question: would there be any problem using backup power for computer use?
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....." can you connect a 10kW to the whole house panel?..."
the short answer is no.
you are about 38Kw short ....... if your service is 200 Amp
and about 14Kw light if it is 100A
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, wer ist jetzt der Idiot ?
With the proper transfer switch you can connect any generator to the house's main panel. Whether you want to or not is a good question, but you can do it. Especially if you have automatic startup and cutover, you want to make sure that the load the generator will see is within it's ratings, even if you're not there to take care of it.
10KW is about 40A at 240V, not enough to guarantee you can pick up the entire load on the typical modern home, if you're using electric for any of: heat, hot water, dryer, range, AC, etc. You need some sort of load-shedding mechanism, and that's what the multi-circuit transfer switch effectively accomplishes.
Now, if you have a manual cutover system, and if you're sure you (or whoever is doing the cutover, half asleep in the middle of the night) will be alert enough to shut off the big loads, then you can use a main panel transfer switch.
I run my whole house off a 10 kW genset during outages, including heat pump.
You do need to have your CB panel well labeled and know the loads.
For instance, when we need the heat from the heat pump, the resistance strips in HP are on separate circuit for which breaker is left open. When HP is to run, the water heater breaker is opened.
Likewise, when using the oven or range the HP and wqter heater breakers are open.
Just about everything else is left on, but you do need to keep a running account in your head (or on a pad next to the panel) about what could come on.
If you can't keep track of loading, the answer is no, you cant hook up the house to 10 kW.
use your computer at your own risk....unless you have an UPS and power conditioners and surge protection, and a faraday cage over your house...
OK you don't really need the cage
the stuff coming from the pole ain't that clean either but it doesn't fluctuate as much as a small home unit could
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, wer ist jetzt der Idiot ?
Actually, your standard PC is pretty much immune to any sort of fluctuation the genset might put out, other than a major overvoltage (over 200V or so on the 120V line). Of course if the voltage dips the computer may reset, but other than that the switching power supply they use eliminates any real dependency on waveform, etc.
If your view never changes you're following the wrong leader
I have not look recently, but it not uncommon for PS to be rated 100 to 250 volts without switching..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
I agree it's just that I'm just a tad gunshy since we lost ours this past July......but it was probably due to one two many blackouts in a short time ...more an ounce of prevention ..
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., wer ist jetzt der Idiot ?
Certainly high voltage (kilovolt) surges (eg, due to lightning) can do in a computer, but otherwise they're pretty rugged from a power standpoint. What often happens with power outages is that fans fail to restart after one and something overheats.
If your view never changes you're following the wrong leader
I've put in a lot of lpg gen-sets with transfer switches and many people chose to convert their fau to propane also or put in pellet stoves to back up the heat.
You seen to be under the misperception that this thread's about backup generators. ;)
If your view never changes you're following the wrong leader
I agree the thread is about the circuits, I was pointing out some of the ways people get around stacking the kw up against the panel. Everything in this area is all electric, at 1.5 cent a kilowatt it's only recently that people have been using alternate sources to supplement their electric heat.
No, actually it was about computers, but only briefly before it drifts into drywall or some such.
If your view never changes you're following the wrong leader
You know now that you mentioned it these pellet stoves do a fine job drying drywall mud, particularily if they are on a generator backup.
Ya gotta be kidding, 1.5 cent a killowatt?
"High-tech companies come here for the nation's cheapest hydroelectric power rates, thanks to Grant County's two enormous dams, which pump out power as cheap as 1.5 cents per kilowatt-hour, said Tim Snead, the city's administrator. That compares with a national industrial rate of 9 cents. The data centers gobble up 40-plus megawatts of electricity each."
Yep this is the last home of cheap power but the rates will eventually have to realign.[the quote was from the business section of the SeattlePI, March 14, 2007]
Good intro article on this topic in JLC this month.
Jim
Never underestimate the value of a sharp pencil or good light.
can you connect ... to the whole house panel?
Simple answer = no.
You need a separate panel loaded with the circuits the generator can handle. The crossover switch is fed by the main panel and the generator. It feeds the sub panel.
Complicated answer: Why $$$$huure it can (|;>)
SamT
Edited 10/1/2007 8:05 pm by SamT