2 Buildings...2 Services...1 Generator?

[shortcircuit2]

Ok, we all questions about generator installations this year. I've searched the forum but can't find a discussion related to this situation.

I have a customer with a detached garage with its own service and utility meter along with the home that has its own service.

Can we provide optional standby power from 1 generator to both services without violating the code?

Thanks, shortcircuit

 

[qcroanoke]

Ok, we all questions about generator installations this year. I've searched the forum but can't find a discussion related to this situation.

I have a customer with a detached garage with its own service and utility meter along with the home that has its own service.

Can we provide optional standby power from 1 generator to both services without violating the code?

Thanks, shortcircuit

NEC violation aside, I don't see how you could do it with just one transfer switch,(not that you said you were going to try to) my thinking is you need 2 transfer switches minimum.

 

[ceb58]

NEC violation aside, I don't see how you could do it with just one transfer switch,(not that you said you were going to try to) my thinking is you need 2 transfer switches minimum.

That's about the only way to do it. I would question the need to power the garage in an outage.

 

[Open Neutral]

If they will settle for lighting in the garage; you could put in LV backup lighting powered by the generator, and avoid all of the issues.

 

[shortcircuit2]

Yes...with 2 transfer switches. The detached garage has an art studio on the 2nd floor, a refridgerator with drinks and food, and a furnace for heat. It needs generator power also.

Ok...it will be one feeder that supplies 2 buildings. Each building having its own grounding electrode system. So the generator feeder is connected to 2 grounding electrode systems...

I can't think of a code violation?

 

[qcroanoke]

Yes...with 2 transfer switches. The detached garage has an art studio on the 2nd floor, a refridgerator with drinks and food, and a furnace for heat. It needs generator power also.

Ok...it will be one feeder that supplies 2 buildings. Each building having its own grounding electrode system. So the generator feeder is connected to 2 grounding electrode systems...

I can't think of a code violation?

You can still have 2 services, 1 generator and 2 transfer switches. The generator would feed the emergency side of both transfer switches. Wether that's legal or not I will defer to others who know more about what the code says than I.
Also, are they automatic transfer switches or manual transfer switches? If automatic you need to think about the start circuit and which service will handle the coolant heater and battery charger.

 

[shortcircuit2]

Ok...with 2 automatic transfer switches. Generator behind garage with main transfer control there...then the house would have a slave transfer switch signaled from the main transfer switch.

Although...if the house were to loose power for some reason and garage still had it...the owner would have to manually start the gen-set and manually transfer the load...right?

Lets say we use a Kohler 20kw gen-set with the RDT transfer switches...

 

[iwire]

I don't see how you could do it with just one transfer switch,(not that you said you were going to try to) my thinking is you need 2 transfer switches minimum.

I agree and it is how we have done it.

 

[texie]

2 transfer switches, either 1 can call for generator start. Pretty straight forward. But off the top of my head, I question if solid neutral transfer switches would be OK as they are 2 separate services (not feeders from the same service). I think switched neutrals with a seperately derived generator would be in order .