Size of Generator

[Anthony Korculanic]

I have varying opinions on the size of generator I need for my house. I just got a 45kw generator on the recommendation of my electrician but the people I bought it from said it is way too small for my house. I have asked around and everyone seems to think that the 45kw will be more than enough. Just wondering what people here think. My house is 6,000 sq ft and has 4 AC units. My main breaker is 200 amp, 250V, 3 phase.

Anthony Korculanic

[M Miller]

I don't have the knowledge to answer this but also consider if your a/c units are heat pumps with the back up heat strips you will need to be able to power the compressors and heat strips at the same time. These strips use a lot of power. This was a concern on my installation with 2 heat pumps and only one used the strips (the other was gas bkup) and I was considering a 16KW generator.

[Slice]

some strange things here you have 3 phase power ?


and 4 a/c on 200 amps must be small a/c units..


seems mot enough to start those a/c units depending on thier size mine is a 65kw and i have 2 1.5 tons ac when they start i know as the generator bogs down and lights flicker.....

what part of the country ?

[Bill Liedtke]

If you truly have 45 KW, and also truly have 3 phase, you are sized fine. I have 4300 sq. ft. and could care less about air-conditioning during emergency power outages, so 15 kw will run my house easy except for the A/c. That DOES include a well pump, a septic pump, and an electric dryer amongst other things such as fridge and electric cook top and micro wave and all tv's lighting, etc. Depends on what you want generator power for: emergencies or as a substitute for the utility company.

You have enough to be the later with 45 KW. What does it run on?

Bill

[Anthony Korculanic]

The house is three phase because I live in the Bahamas and thats the way they do it down here. I want it to run somewhere between for emergency purposes and like the utility company. I have a newborn child and my 70 year old father living here so we would like to be able to take care of all of their needs during an outage which would include keeping the AC running.

[Kelly Myers]

In order for me to help you out here, I will need much more information.

Please post up the LRA numbers that appear on the name plate of each motor in the house, including the air condensors.

If you haven't already had it done, I would suggest putting time delays on two of the 4 condensors.