Got a generator: Do I have 100 volt or 200 ?

Waterfish · 01-11-2004, 05:19 PM

After having no electricity most of last week due to the storm (not to mention the road I live on being closed by huge snow drifts), Friday I bought a 5000 amp Generac generator. To connect this to the service in my house, I am ordering a "Genrac" panel from Platt Electric. Before they order this panel, they need to know whether I have 100 volt service, or 200 volt service. I checked all my breaker boxes, and the box on the house where PGE reads the meter, and nowhere could I find anything that says whether I have 100 volt or 200 volt service. Do any of you electrical experts know how I can tell which I have?

Silver Hilton · 01-11-2004, 06:00 PM

If you have an electric stove or dryer, odds are pretty good that you've got 220. If your house is newer than 1980, it almost certainly has 220.

Fshklr · 01-11-2004, 06:14 PM

I believe you mean 100 or 200 amp service.
Breaker panels would mean probably 200 amp service for 120 - 240 volts.

Fuse breakers,glass style, flip bar connectors, really old pre 1960-65? are not 200 amp service.

there should be some kind of sticker or plate or factors inlaid stamp that says 125, 200, 225 etc amps...All new homes are at least 200amps or more.
hope this helps.
I am currently at my girlfriends in an old duplex..really old..the plate say 200amps with 120 to 240 volts-AC...200 amps :smile:

freespool · 01-11-2004, 06:14 PM

Are you sure they didn't ask you if you had 100 or 200 amp service? Most newer circuit breaker panels are 200 amp service.

salmon hugger

Fshklr · 01-11-2004, 06:18 PM

I just re-read your post..you said you checked ALL the breaker panels???if it was a 200 amp service there would only be 1 panel with multiple light switch types inside...if you have fuses or multiple fose panels I am not very knowledgeable about those.

R Jackson · 01-11-2004, 06:18 PM

And are you sure you didn't buy a 5000 watt generator? I agree with Freespool on the amp service too.

kenai · 01-11-2004, 06:33 PM

Platt indeed wanted to know it you have a 100 or 200 amp service. All residential services are 240 volt (well almost). The generator is 5000 watts not amps. 5000 amps is enough to run a small factory.
I've installed several of the Platt genrac panels, they are very simple transfer switches, make sure you follow the directions exactly or you could potentially backfeed the transformer and the power company would be seriously upset.

Your breaker panel probably says somewhere 240/120 VAC on the labeling. The double pole (handle) breakers indicate the 240 volt circuits. Email me if you have any questions on installation.

DAB · 01-11-2004, 06:43 PM

If you are going to hook up your generator to your Panel board in your house, and since you are unshure of the service voltage or amperage of what you have in your house. I STRONGLY ADVISE YOU TO HIRE A QUALIFIED ELECTRICTION TO DO THE WORK. Because if you hook it up to the WRONG side of your main breaker, and do not turn the correct breaker off,when the power comes back on I do belive you will have real trouble in river city. I do know how but am unwilling to say in case some one does it wrong, then it would be my bu-tt, in the sling, and I would venture to say 99% of people would agree with me.
Better safe than sorry.--- Good Luck.
DAB -------- KENAI made a very important point that I forgot about, back feeding the transformer, what back feeding would do is make the power lines hot and dangerous ( deadly )for the power co.
DAB

[ 01-11-2004, 07:57 PM: Message edited by: DAB ]

roadsend · 01-11-2004, 06:50 PM

If you can't find the plate with the amperage of the service entrance, look at the wire size. Check it against the chart in a manual such as "Wiring Simplified" to determine maximum amperage of the wire which will likely be close to the amperage of the service entrance breaker box.
Have an electrician install your switchover equipment.

Waterfish · 01-11-2004, 06:56 PM

Thanks for the information, and you guys are right, my generator is 5000 watts, not amps (I guess a 5000 watt generator wouldn't even have fit in my pickup).

Our house was built in 1995. The main breaker box is in the garage, and another breaker box (coming off the main breaker box)is in the well house, which is also attached to the house. I have a shop too, and the breaker box in the shop comes from the breaker box in the well house. The shop has 220 volt plug-ins for a welder. I just looked at the circuit breakers again, and some of them are double pole (handle) breakers, and they are stamped with "120/240 VAC.
So I assume this means I do indeed have 200 amp service? Yes, I will have an electrician do the hook up, but I want to get all the parts before hand so it will be ready for him to complete in one trip to the far country of the Zigzag territory.

[ 01-11-2004, 08:00 PM: Message edited by: Waterfish ]

roadsend · 01-11-2004, 08:08 PM

Based on your latest post it is likely you have at least a 200 amp service. Having the electrician do the install is a smart move. Bear in mind that your 5000 watt generator will no where near run every circuit in your house as it is only the rough equivalent of 40 amps at 110V and 20 amps at 110V. When the generator is on, use your small appliances sparingly and your big ones not at all.
With my 5000 watt generator, I use only water pump, freezers, refrigerator and some lights.

kenai · 01-11-2004, 08:24 PM

Also if you have a gas furnace or non-electric heat, you can supply the fan of the furnace with a cord and plug circuit and even have heat during an outage.Ask your electrician to do a load calculation. Put a couple of lights on the e-panel, the fridge and the furnace fan and your good to go at 5000 watts.

Waterfish · 01-11-2004, 08:42 PM

Roadsend and Kenai,

During a power outage, supplying power to a few basic things are all I care about, namely the freezer, refrigerator, and well pump. We heat our house 100% by wood heat, so power for heat isn't an issue. And we have oil lamps, a Coleman stove (set next to an window open) and a gas barbeque. During this last outage, I was beginning to worry about losing a whole freezer full of deer, elk and fish. We were just about to load up all the meat and take it to a friend's freezer when the power came back on. So if a 5000 watt generator will power those three things, I will be happy (although it would be nice to use the computer to check Ifish!).

roadsend · 01-12-2004, 03:55 AM

"supplying power to a few basic things are all I care about, namely the freezer, refrigerator, and well pump. "

If these are the only things you need to power, why bother with a panel switch over? why not plug them in direct?
I installed a #10 wire 220V extention from the garage to the water pump which I can maually plug in to the generator after unplugging the pump from house power and plugging into the extention. I use regular extentions for my two freezers and refrigerators and my floor and table lamps.
Not using any part of your house wiring system eliminates the possibility of backfeeding power into power company lines and reduces the likelihood of overloading the generator.