180115-1043 EST
I have to assume each 30 A outlet has its own breaker or fuse.
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180115-1043 EST
I have to assume each 30 A outlet has its own breaker or fuse.
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If the marina is going to be busy, you really need to keep the Information Note in mind.
555.12 ... Informational Note: These demand factors may be inadequate in areas of extreme hot or cold temperatures with loaded circuits for heating, air-conditioning, or refrigerating equipment.
Don, Illinois
(All code citations are 2017 unless otherwise noted)
I agree. It doesn't make sense. I have never seen this done before. My main reason for questioning it, along with the calculated load being reduced so far. You mentioned splitting the loads for 120v. Maybe that has something to do with it?? One other thing about this pedestal feeder: as the chart indicates, it is (9) 120/240v 30a receptacles for the load calculation. But each of the (5) pedestals has a 20a/120v GFCI receptacle that is dropped from the calculation, as allowed by NEC table 555.12, note-1. Any thoughts on this additional info?
Again, I want to understand why he chose this method, as I may have to split-up or add some circuits and want to stay consistent.
Thank you,
JB78
how many pedestals?
how many and what type of recept on each ?
where does the 9 come from if there are 5 pedestals?
180115-1229 EST
Are these 240 V receptacles? If so then 9*30 would be the number to use. But, still if the source is 270 A, and the receptacles are 30 A, then protection is needed at each receptacle.
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Right. Five pedestals on this circuit. Four of them have (2) 30a, 120/240v recept. and (1) 20a/120v. The fifth pedestal has (1) 30a, 120/240v and (1) 20a/120v. That's where we get (9) 30a, 120/240v for calculations - the 20a receptacles are not counted (table 555.12, note-2). All receptacles have individual OC protection in the pedestal.
JB78
he is only using 1 30 from each pedestal
not 2 if it has 2
5 x 30 x 0.8 x 0.9 = 108 A
the note is not clear
it says use the largest
it does not address if you have 2 'largest'
Although it does not say it explicitly, my impression is that the reason for only counting the largest circuit is the assumption that if there are two circuits of different size per pedestal that only one of them will be used at a time and the two circuits are to accommodate different connection needs for different boats, not that two boats will be connected to each pedestal.
If the OP's design is for 35 pedestals for a 70 boat marina, then he would have to count both before applying any diversity factor.
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