Panel tap

[Jim W in Tampa]

Can i tap the main lugs of the first sub panel on a 400 amp service to feed a 100 amp breaker that services a 30 circuit 200 amp panel.It will be in emt and about 20 feet run? 3 phase y 120/208 if that matters.The 200 amp panel has a main breaker of 100 amps.Main panel is lugs only and can take 2 sets of wires under same lugs and protected by 400 amp breaker outside at meter bank/disc.

 

[woodduder]

If you follow the rules for feeder taps, then you are good to go.

 

[RUWired]

Jim, The 25' tap rule is 1/3 the rating of the breaker suppling the feeder.(400x.333=133amps).At 75 degree the minimum would be 1/0 cu.
Rick

 

[infinity]

Jim,

Maybe it's just late, but I've read your OP ten times and still can't figure out exactly what you have.:-?