Questions: 600 amp 240v single phase service panel and 600 amp rated transfer switch

[jango]

My uncle in southern CA wants to upgrade his electrical service to a 600 amp service and he also wants to have a whole-house generator and transfer switch set up. Can I get some direction/feedback on a schematic plan/sketch drawing that would likely be the most efficient and feasible method for this system to be set up? Any help/direction would be greatly appreciated. I'm currently planning on having three 200A sub panels being fed. Some questions I have are: 1.) Can I get a 600A rated automatic transfer switch that can also take the place of a CT transformer (or would I still need both?) Also, any sort of direction or rough sketch showing details would be ever so appreciated. Thanks!

 

[augie47]

As has been discussed in earlier threads when you mention an ATS you open up a whole can or worms because of the wording of 702.5. ('08 Code)
If you attempt to transfer the entire calculated load of the residence the generator will need to carry that entire load in which case your uncle best have deep pockets.
More often, a decision is made to transfer selected loads in which case you would probably transfer one or two of your panels.

 

[jango]

Thanks Augie, let's assume then that I will be providing generator back for one (or two) of the sub panels. Can I still get some feedback/sketch ideas on the wiring schematic of such a system? Thanks so much.

 

[LarryFine]

Thanks Augie, let's assume then that I will be providing generator back for one (or two) of the sub panels. Can I still get some feedback/sketch ideas on the wiring schematic of such a system? Thanks so much.

It's really too simple for a sketch. I suggest using one 200 ATS and supplying one panel of generator loads. It should be easy to choose one panel's worth of loads if he's realistic about what is necessary to power.

The POCO usually chooses the metering scheme, so find out who your POCO-assigned field engineer will be and discuss the CT setup with him, as well as how and where the one set of conductors will become three.

You will need to have either a single 600a disconnect or three 200a discos; the latter may be cheaper. If the latter, the T/S will either have to be service-rated and grouped with the other disco's, or be supplied by one of three discos.

 

[dbuckley]

in which case your uncle best have deep pockets.

Uncle has a 600A service and is looking for a "whole house" generator: how many shallow pockets have a 600A service?

 

[LarryFine]

how many shallow pockets have a 600A service?

Maybe the question should be: "how many people with 600a services nonetheless behave like they have shallow pockets?"

 

[dbuckley]

Maybe the question should be: "how many people with 600a services nonetheless behave like they have shallow pockets?"

"All of them".

That's how their pockets got to be quite deep.....

 

[ceb58]

It's really too simple for a sketch. I suggest using one 200 ATS and supplying one panel of generator loads. It should be easy to choose one panel's worth of loads

You will need to have either a single 600a disconnect or three 200a discos; the latter may be cheaper. If the latter, the T/S will either have to be service-rated and grouped with the other disco's, or be supplied by one of three discos.

This would be the best way to go. Go with a S/E rated ATS it will have the main breaker in it for the utility supply. If you need to go with two then use two S/E ATS and parallel the start wires to the gen. This way it will control both ATS. Depending on the rating of the gen. you could get a disco. with double lugs to feed the ATS's generator side of the switches.

 

[mbeatty]

I agree with LarryFine and ceb58. Good advice.