30 amp feeder, only two circuits?

[gporter]

I would like to supply a small picnic pavilion with a 30 amp 120/240 volt feeder. The only loads would be lights and receptacles. Refering to 2002 NEC Section 225.39(B), the code requires that a feeder rated at 30 amps can supply a panel with a maximum of only 2 circuits on it. Restricting the number of circuits does not seem to make sense, if the feeder is sized according to the branch circuit and feeder calculation rules. My 2 circuits will never be able to reach 30 amps, so why the restriction?

For example:
120/240 volt feeder at 30 amps can supply 7200 v-a.
A single 120 v 20 a circuit will draw only 2400 v-a. Two of them will draw a maximum of 4800 v-a. So why does the code restrict you to only 2 circuits? I could understand this if my feeder was only 120 volt.

 

[bob]

Re: 30 amp feeder, only two circuits?

I think you are applying the wrong section. Look at 225.7. Are you installing a branch circuit or feeder. Will you have a breaker panel at the pavilion?

 

[iwire]

Re: 30 amp feeder, only two circuits?

If you need more than two, two wire circuits you are stuck with a 60 amp feed minimum.

I do not know why, but knowing why would not change the requirement.

Could you bring out branch circuits instead of one feeder?

2002 NEC
225.39 Rating of Disconnect.
The feeder or branch-circuit disconnecting means shall have a rating of not less than the load to be carried, determined in accordance with Article 220. In no case shall the rating be lower than specified in 225.39(A), (B), (C), or (D).

(B) Two-Circuit Installations.
For installations consisting of not more than two 2-wire branch circuits, the feeder or branch-circuit disconnecting means shall have a rating of not less than 30 amperes.

(D) All Others.
For all other installations, the feeder or branch-circuit disconnecting means shall have a rating of not less than 60 amperes

 

[gserve]

Re: 30 amp feeder, only two circuits?

Can't he have a disconnect rated 60A but put in a 40A main breaker if his calculated load is per article 225? And then add more than 2 circuits?