Panel as a tap can

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Red Forman

Red Forman

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Longview,Texas
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Electrical Designer
I have come across a redesign project where the client wants to move breakers out of a panel to a new sub panel that will be fed with feed-thru lugs in the original panel. All breaker slots in the panel feeding the sub will have blanks installed leaving no exposed live parts essentially turning the panel into a tap can.
Is there anything in the NEC prohibiting this?
 

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No.
But I need to look at your drawing on a larger screen
Did I see an 8 awg egc ( not ground) with 3/0 from a 200 A OCPD?
 
Red Forman said:
I have come across a redesign project where the client wants to move breakers out of a panel to a new sub panel that will be fed with feed-thru lugs in the original panel. All breaker slots in the panel feeding the sub will have blanks installed leaving no exposed live parts essentially turning the panel into a tap can.
Is there anything in the NEC prohibiting this?
Click to expand...
Thanks for the quick response. Just for some clarification, the new panels are 300' away from the existing panels. The oneline shown is what was originally planned until they started VE'ng the project.
 
Btw, my mistake. They are not eliminating the OCPD enclosures. Otherwise they would need 300' of 400A wire.
Thanks again, This forum is indispensable.
 
If you upsize the ungrounded for you will need to make proportional adjustment for EGC, per 250.122
Look at percent increase in CM, change egc to cm, increase by percentage, change back to awg
 
The 6 AWG EGCs in with the feeder conductors to the 200 amp disconnects are too small....they need to be 3 AWG
 
I have a question I am attempting to follow. So please forgive me in advance.
Utility feeding main exhisting installed in the same building as LVT and OCD 1 and 2
The LVT stays
GEC at LVT (SDS)
The main breaker is removed from section one (old first disconnecting means) and this is a tap can now
Assuming the SSBJ is sized correctly to the Tap can.
The (2) 200 amp OCD stays
Would these two 200 amp OCD be the first disconecting means after the SDS
If so would the EGC not be an SSBJ 250.30(2) and be sized per conductors in the raceway (250.30 (2) a and 250.102 (C)) to OCD 1 and 2 and require a #2 SSBJ for the 3/0 cu ungrounded conductors to OCD 1 and 2
Than an EGC after the 200 amp OCD to new P1 and P2 (250.122) 3/0 cu 200 amp #6 EGC

Thank you in advance for helping me follow correctly.
 
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