Oversized conductors on 400 a breaker

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Onexl85

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Location
NY
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Electrician
Have a long 400a 208v run that had been oversized to 4 sets of 500MCM. Problem is the gear is very tight and would be a bear to run those four sets to the Breaker as well as finding a 400a breaker that will accommodate 4 sets of 500MCM!

is is Legal junction those four sets adjacent to the gear and run a single set to the breaker?
 
You could probably just set a trough and use one wire sized for 400 amps tied to the parallel set. The voltage drop will be handled the rest of the way.
 
I thought it was Legal, would you happen to know a code reference?
About 500 feet, it’s overkill but you know engineers!
 
A single 500 kcmil is permitted. There is no specific code reference. 500 kcmil is good for 380 amps, next size up rule 400 amp OCPD is permitted. 240.4(B) is for the next size up rule.
 
Common remedy.. put one of these in a j box or wireway.. one conductor to your breaker
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