New whole house generator and ATS

D

dekeSC

Owner
Location
South Carolina
Occupation
Electrical Contractor
I will be installing a new whole house generator with an ATS on an existing house with the meter and 200 amp main breaker located outside and feeding a 40 circuit panel inside. I have not confirmed this yet, but if there is 4/0 SE cable from the outside meter to the house panel (2 hots and a bare ground). My question is now that there will be a service rated ATS next to the outside meter will I have to pull new SER cable 2 hots, a neutral and a ground to the house panel and separate all the grounds and neutrals in the house panel?
 
dekenselectrical said:
I will be installing a new whole house generator with an ATS on an existing house with the meter and 200 amp main breaker located outside and feeding a 40 circuit panel inside. I have not confirmed this yet, but if there is 4/0 SE cable from the outside meter to the house panel (2 hots and a bare ground). My question is now that there will be a service rated ATS next to the outside meter will I have to pull new SER cable 2 hots, a neutral and a ground to the house panel and separate all the grounds and neutrals in the house panel?
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Okay, I was given incorrect information. The existing service is a 200 amp meter without a main breaker feeding a panel with a 200 amp main breaker. The cable from the meter to the panel is 4/0 SE cable 2 hot's and a bare ground, all the grounds and neutrals on the same bus. The house panel is completely filled with approximately 44 circuits and a sub panel next to it. The sub panel is fed with SER cable 2 hot's a neutral and a ground. So my question is if we add the ATS that is service rated will I be required to pull new SER cable from the ATS to the house panel and separate the neutrals and grounds?
 
dekenselectrical, please update your profile to show an accurate location and occupation.
 
dekenselectrical said:
Okay, I was given incorrect information. The existing service is a 200 amp meter without a main breaker feeding a panel with a 200 amp main breaker. The cable from the meter to the panel is 4/0 SE cable 2 hot's and a bare ground, all the grounds and neutrals on the same bus. The house panel is completely filled with approximately 44 circuits and a sub panel next to it. The sub panel is fed with SER cable 2 hot's a neutral and a ground. So my question is if we add the ATS that is service rated will I be required to pull new SER cable from the ATS to the house panel and separate the neutrals and grounds?
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Yes. From my understanding of the rules you would bond neutral and ground in the ATS and separate neutral and ground from there.
 
Is there an exception when you would not be required to pull new SER cable from the ATS to the panel and separate the ground and neutrals?
 
I've been confused about the exception and think it depends on what code cycle

But can't you just put "not service disconnect " label to make it legal?

Not sure, but since no ones answered since Friday, maybe this will get the attention of someone that knows.
 
dekeSC said:
Is there an exception when you would not be required to pull new SER cable from the ATS to the panel and separate the ground and neutrals?
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There is not any exception that would allow you to keep the 3 wire cable.

Additionally, if the house main panel is labeled “Only For Service Entrance”, you can’t separate the neutrals and grounds in that panel, and you will have to replace that panel as well.

I do about 12 generators a year, and look at probably twice that amount that the customer decides not to go ahead with. and they are usually more complicated and expensive than anyone wishes.

Very few houses are set up for a second power source for the start, and it’s not uncommon to have to perform a good bit of restructuring to get them to work.
 
I'm not sure if it's labeled “Only For Service Entrance” and I know it will be a giant pain in the butt, but can I just pull new SER cable from the ATS and add ground bars and seperate the ground and neutrals?
 
dekeSC said:
I'm not sure if it's labeled “Only For Service Entrance” and I know it will be a giant pain in the butt, but can I just pull new SER cable from the ATS and add ground bars and seperate the ground and neutrals?
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From the ATS to the main panel, which will become a sub panel, you’ll need 4 wire. From the ATS to the meter you must use 3 wire, make your N-G bond in the ATS, which is now you first disconnect, and you need an SE-Rated ATS.
 
Yeah, that's my main concern because the panel is stuffed. If you run into this do you normally just replace the entire panel, or take the time to make room for the neutral bars?
 
dekeSC said:
Yeah, that's my main concern because the panel is stuffed. If you run into this do you normally just replace the entire panel, or take the time to make room for the neutral bars?
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Why add a neutral bar? Unless it’s one of those service equipment only panels, remove the bond screw or jumper, add ground bars and move all the grounds. If it is a service only panel, then you will have to change out the panel.
 
Is this a CA thing?
How far can the unfused service conductors go in a house in CA?
Here for as long as I can remember the service disconnect is required to be
either outside or inside "nearest the point of entrance of the service conductors."

One time many years ago I got really burned by this doing a panel change, so its burned in my memory
old fuse box service was hard to remove, lots of RMC, so I wanted to keep that as a jbox.
I routed new service cable just one extra stud bay 16" extra to reach the service new panel and promptly failed the inspection since I was not 'nearist the point of entry or adjacent their to'.
And even if you could get a EM disconnect ATS, on 'generator mode' you'd still be a feeder and it would need to meet 215.6
 
The panel is currently fed from the meter with SE cable, so my plan was to pull SER cable from the ATS to the panel and separate the grounds and neutrals
 
This is the house panel, I was planning on adding ground bars and separating the grounds and neutrals. Yes, it's a hot mess.
 

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Looks like you have a solid plan, new SE-R and thats a newer good panel it will clean up fine, I dont see a GEC so prehaps its alredy in the meter?
Earlier when you mentioned it would be difficult I was thinking you had a long run of cable inside a finished house. If the customers service cable extends well into the dwelling beyond the point of entry, I would tell them they already have a non-compliant install that should be addressed generator or not. I know some AHJ have local rules that are different.
 
Thanks for confirming I'm on the right track. Yeah, it won't be so difficult getting the SER cable from point A to B it's just getting the grounds moved that's going to be a pain.
 
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