Must float main panel connected to service-entrance ATS?

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TimWA

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Have installed a service-entrance ATS with it's utility input fed directly from service-meter load lugs. ATS output is to the main breaker of the main distribution panel. These two panels are side-by-side in the garage.

Since the ATS with it's main breaker is now first disconnect, do I have to rip apart the pristine make-up job in the main panel to float neutrals? The two panels are literally a foot apart. Hoping I can just keep the neutral-ground strap in the ATS, and the main bonding screw in the main panel.
 
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GoldDigger

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Have installed a service-entrance ATS with it's utility input fed directly from service-meter load lugs. ATS output is to the main breaker of the main distribution panel. These two panels are side-by-side in the garage.

Since the ATS with it's main breaker is now first disconnect, do I have to rip apart the pristine make-up job in the main panel to float neutrals? The two panels are literally a foot apart. Hoping I can just keep the neutral-ground strap in the ATS, and the main bonding screw in the main panel.

If you install an ATS which also switches the neutral you may be able to avoid the whole problem.
If not, then even for a distance of only 24" you will be in violation.
Once possible exception is if the ATS and Main panel are not connected by metal raceway.
 

augie47

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If you install an ATS which also switches the neutral you may be able to avoid the whole problem.
If not, then even for a distance of only 24" you will be in violation.
Once possible exception is if the ATS and Main panel are not connected by metal raceway.
I may be overlooking something obvious, but I don't see where the metal nipple comes into play other that it being allowed to be the equipment grounding conductor between the ATS and the separated equipment grounding conductors..
Per 250.24(A)(5) you would still not be allowed to connect the grounded conductors to the grounding conductors on the load side of the service disconnecting means, in this case the ATS
 

ActionDave

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Have installed a service-entrance ATS with it's utility input fed directly from service....Since the ATS with it's main breaker is now first disconnect, do I have to rip apart the pristine make-up job in the main panel to float neutrals?
Yes you do.
The two panels are literally a foot apart.
First disconnect is where the line is drawn. Does it always make sense? No. But the line has to be drawn somewhere.
Hoping I can just keep the neutral-ground strap in the ATS, and the main bonding screw in the main panel.
No, you can't.

Is this your own house?
 
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