nerspellsner
Member
Can a 62 amp 15kw generator be used with a 200 amp automatic transfer switch powering a 200 amp panel with a 150 amp load?
generator size with auto transfer switch
- Thread starter nerspellsner
- Start date
- Status
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
Not unless you keep the load below the generator's breaker rating.
It's done all the time, but what happens if, say, it's summertime, you're away from home, and the power goes off. (Never happens, right? :roll: ) The A/C is probably going to overload the generator. Or, it's the dead of winter, and the electric furnace wants to come on.
An interlock that drops out the A/C compressor or electric heat during unattended use, would be a good idea, and easy to design; for example, a 240v relay with the coil on the line side of the ATS and the N/O contact in series with the A/C 24v. line.
You could even add a manual override to reenergize the A/C or heat after you come home and begin shedding some other loads. The point is that a genuine 150a load is a lot, and it sounds like an all-electric house; I suggest a 25Kw generator.
It's done all the time, but what happens if, say, it's summertime, you're away from home, and the power goes off. (Never happens, right? :roll: ) The A/C is probably going to overload the generator. Or, it's the dead of winter, and the electric furnace wants to come on.
An interlock that drops out the A/C compressor or electric heat during unattended use, would be a good idea, and easy to design; for example, a 240v relay with the coil on the line side of the ATS and the N/O contact in series with the A/C 24v. line.
You could even add a manual override to reenergize the A/C or heat after you come home and begin shedding some other loads. The point is that a genuine 150a load is a lot, and it sounds like an all-electric house; I suggest a 25Kw generator.
- Location
- Massachusetts
Larry's answer is a common sense approach to good design. 
I will give you an NEC answer.
As long as this is an optional standby generator you can do exactly what you describe.
If this is not an optional generator than the rules require it to be able to drive the entire connected load.
I will give you an NEC answer.
As long as this is an optional standby generator you can do exactly what you describe.
If this is not an optional generator than the rules require it to be able to drive the entire connected load.
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
- Occupation
- Electrician
Yes it all depends on what you want to run off it and how much you want to pay. We did a job once where the HO wanted an automatic genset. We ended up having to go with something like a 20 kw because he wanted to be able to use his electric range. If it were me, I would have bought a 10 kw genset, a 40 dollar propane coleman camp stove, pocketed the extra grand or two and taken a week off 8)
- Status