I have done a lot of generator installations, trouble shooting and servicing.
I also ran my home on a small diesel generator for a time. I found that the biggest cost was running the generator when there was no load. During the night the load was mostly zero, but the plant had to be running if a refrigerator or freezer cut in. It also had to be available for the well pump or the furnaces.
I used a 6 KW set and found it to be the "sweet spot". We did not use the electric clothes drier as any motor load trying to start while the drier was on would trip our main generator breaker.
Yes, I know there are load sensing automatic start sets available. At minus 20 or 30, I chose not to trust an automatic start. Also, adding a load sensing automatic start to an existing set is not cheap. I didn't have time to home brew one either.
The cost of a plumbing freeze up was another factor.
If you have natural gas available there are some economical NG sets available.
I would consider a 5 KW set a little light for a 50 amp starting surge. You may have issues with voltage dip, or it may work to your satisfaction. The set has a good chance of starting the motor but other loads may have issues with the voltage dip.
If this is at 120 Volts consider reconnecting the motor for 240 Volts.
Are you intending to buy a set or are you using an existing set?
Is this standby or prime power?
Where in the world are you?
Bill
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"Why not the best?"
Jimmy Carter
