NEC 230.2c1

[s.d. cronk]

NEC 230.2c1 states that "additional services shall be permitted where the capacity requirements are in excess of 2000 amperes at a supply voltage of 600 volts or less"
A debate has occurred here in regards to the reference of "capacity requirements".

Does this mean that the first service will need to have a capacity in excess of 2000a and thereby allow a second service to "pick up" the remaining load that would be in excess of the 2000a?

Or does it mean that the combined service capacity will be in excess of the 2000a and thereby allow you an additional service and permit you to separate the loads as you desire, such as two services of 1200a each?

Or does it mean that the building has a calculated load in excess of 2000a and thereby allow two services consisting of either of a 2000a for the first and a second service for the remaining or two services of 1200a each for a total that would exceed the 2000a benchmark?

Or are all three convoluted amongst themselves and we are completely off base?

Thoughts?

 

[612278]

Re: NEC 230.2c1

Hi sd cronk

I think a service that size would have to be engineered and anwsered by the local utility.(possible new sub-station).There are many questions. Service entrance conduits big enough for additional utility wires for both services. Available local power etc.

steve

 

[charlie b]

Re: NEC 230.2c1

The confusing part of the wording is the phrase ?capacity requirements.? That is not the same as ?capacity.? It is not necessary that you install the first service with a 2000 amp capacity, and then put the remaining load on the second service. Rather, you first compute the requirements. That is, you perform an Article 220 Service Load Calculation. If the results are above 2000 amps, then you are allowed to use two services.

The article you cited is worded in a permissive context. You are permitted to install more than one service to a single building if you meet any of the criteria. You don?t have to have two services, but you may if you wish.

Therefore, I would infer that any combination of service arrangements would be allowed, once you can show that the total load is over 2000 amps. If for example, the total load is 2400 amps, then you can have a pair of 1200 amp services, or a 2000 amp service next to a 400 amp service, or any other combination that you desire (and that the utility is willing to provide).