CEBen
Member
- Location
- Casper, Wyoming
We have an engineered job for a Residence Hall. The main breaker is outside next to the utility CT Section and is 2500 amps. The switchgear is fully rated. The MDP is 100' away and inside the building. The MDP is Main Lug Only. THe system is 4 wire grounded Y.
The engineer has called out 6 sets of 600 kcmil THHN between the 2500 amp main breaker and the MDP. The inspector is calling for 6 sets of 750 kcmil THHN between the main breaker and the MDP.
Accoridng to the inspector the engineer has sized the wire too small based on the rule in NEC Table 310.15(B)(2)(a) for 4-6 current carrying conductors.
What is the proper wire size between the main 2500 amp breaker and teh MLO MDP to meet NEC 2009 Code?
The engineer has called out 6 sets of 600 kcmil THHN between the 2500 amp main breaker and the MDP. The inspector is calling for 6 sets of 750 kcmil THHN between the main breaker and the MDP.
Accoridng to the inspector the engineer has sized the wire too small based on the rule in NEC Table 310.15(B)(2)(a) for 4-6 current carrying conductors.
What is the proper wire size between the main 2500 amp breaker and teh MLO MDP to meet NEC 2009 Code?