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Discussion Starter · #1 ·
I was talking with a supplier of RV peds, getting some prices, specs...ect. They told me "everyone feeds the loops with a 200 amp breaker. So 7 to 10 sites on this one breaker. But the peds are only rated for 125 amp. I questioned it and they said it always done that way. Opinions?
 

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Discussion Starter · #5 · (Edited)
Pedestals are 125 amp rated, they have a 50 amp 2 pole breaker, a 30 amp single pole breaker and a 20 amp single pole breaker with corresponding receptacles. The feeders are 250 mcm or 4/0 AL. I just don't know how they can feed them with a 200 amp breaker when the ped it's self is rated 125.

 

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The pedestals are only a "tap", if you will, off of a 200 amp circuit. This is acceptable because the pedestal itself will never have more than 80 amps on one phase. (One phase of the 2 pole 50, and the 2 pole 30). The guts of the 1st panel in the "loop" does not have the load of the last pedestal traveling through it. If you do this job, from my own experience in one just like it, take precaution to balance the load correctly. Phase 1 in the first box gets the 30 amp breaker, phase 2 in the second box gets the 30 amp breaker, and so on down the line. Your main breaker will thank you for it.

Edit: 1 phase of the 2 pole 50, and the single pole 30.
 

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Discussion Starter · #7 ·
T&K said:
The pedestals are only a "tap", if you will, off of a 200 amp circuit. This is acceptable because the pedestal itself will never have more than 80 amps on one phase. (One phase of the 2 pole 50, and the 2 pole 30). The guts of the 1st panel in the "loop" does not have the load of the last pedestal traveling through it. If you do this job, from my own experience in one just like it, take precaution to balance the load correctly. Phase 1 in the first box gets the 30 amp breaker, phase 2 in the second box gets the 30 amp breaker, and so on down the line. Your main breaker will thank you for it. Edit: 1 phase of the 2 pole 50, and the single pole 30.
But the loop is landed in the pedestal that has a 125 amp rating. The individual units are figured at 40 amps(9600 VA) I just don't see how the enclosure can be rated less than the feeder supplying it. My inspector is getting a call on this one.
 

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That's the way we did it at a rv park couple years back . As T&K said the load is controlled by the the beakers in the pedestal .
Basically like tapping off a buss.
But when in doubt ask the man in power.
Could save ya from getting bit in the arse later
 

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Discussion Starter · #9 ·
Hmacanada said:
That's the way we did it at a rv park couple years back . As T&K said the load is controlled by the the beakers in the pedestal . Basically like tapping off a buss. But when in doubt ask the man in power. Could save ya from getting bit in the arse later
I've done a few too, but never realized they were only rated 125 amp, some are rated 100 amp. With lug sizes at 350 mcm I never looked. That's how this came up. The supplier asked which one I wanted.
 

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backstay said:
I've done a few too, but never realized they were only rated 125 amp, some are rated 100 amp. With lug sizes at 350 mcm I never looked. That's how this came up. The supplier asked which one I wanted.
Are the feeders to the actual buss coming from the bottom panel where the loops land 1/0 or so.
 

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We added a few sites and while the inspector was there noticed that some of the existing sites had two extra rec added to them. Told us that exceeded the panel rating even though it was fed with 200 amp. Resulted in a little extra work for me which I didn't mind.
 

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Discussion Starter · #12 ·
Hmacanada said:
Are the feeders to the actual buss coming from the bottom panel where the loops land 1/0 or so.
No, the feeders land on lugs that then have short wires going up to the buss that the breakers land on. Maybe that's where the rating comes from.
 

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Discussion Starter · #14 ·
Hmacanada said:
Sorry didn't explain myself well, but that's what I was getting at. Your right IMO , I don't know if they rate the lugs? If the wire fits your good to go.
How many sites do you put on a 200 amp breaker? I like 7, then they can add one in the future. 9 works out to 198 amps of calculated load. 9600VA x 9 x .55
 

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I don't see how this would be any different than running 200 amp wire into a trough and tapping a bunch of 30 amp disconnects off of it. That's common practice.

The only issue I'd possibly have is, does one phase land on a 2 barrel lug? Line and load? Or is one lug bolted to the buss for the line and then another lug is bolted to the buss for the load. Making it so 200 amps is running through a 125 amp buss.
 

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Haven't you ever tapped off a 2000a buss duct with a 200a rated disco?
 

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Discussion Starter · #18 ·
Cow said:
I don't see how this would be any different than running 200 amp wire into a trough and tapping a bunch of 30 amp disconnects off of it. That's common practice. The only issue I'd possibly have is, does one phase land on a 2 barrel lug? Line and load? Or is one lug bolted to the buss for the line and then another lug is bolted to the buss for the load. Making it so 200 amps is running through a 125 amp buss.
The only difference is that a trough isn't rated at XXX amps. I just wish they had a rating for the loop wiring. I understand the buss rating, say you wanted two 50 amp receptacles and a 20 amp receptacle. The ped would be rated to carry that at 125 amps. But if you had a 100 amp rated ped, you could only stick the two 50's in.
 
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