Can one transformer feed two panelboards?

[ElectricPersonality]

I would like to have a transformer located inside a school building feed two panels located in two outdoor trailers. If an enclosed circuit breaker was installed within 10' (secondary length) of the transformer on the secondary side, would it be permissable to install a wireway on the load side of the enclosed breaker and tap off two sets of conductors, one set for the first panelboard and the other set for the other panelboard (i.e. would 240.21 (B)(5) apply in this situation?).

I would like to avoid having to install a panelboard fed from the secondary of the transformer just to feed two more panelboards.

 

[John Arendt]

More info would be helpful. ampacity required at each trailer, xfr size, 'main' cb size (secondary) etc.

You may be able to put two (2) cb's (enclosed) at the wireway; one for each trailer feed, but....more details

 

[augie47]

I somewhat got lost in the details, but a direct answer to your basic question would be "yes". 2008 240.21(C) allows "sets" of conductors to be tapped from a transformer secondary.

 

[woodduder]

You could put double barrel lugs in the XFMR and run two feeds (one for each panel) and use MB panels, if that works better.

 

[John Arendt]

Randy:
Trailers are "outside of the building" & xfr is inside. The OP did not provide enough info

 

[RUWired]

, would it be permissable to install a wireway on the load side of the enclosed breaker and tap off two sets of conductors, .

You'll have to define if your tapping or splicing on the load side of the disconnect in the wireway.If your tapping, ( changing ampacity of conductor rating ) then you'll need additional protection for each of the taps.

Rick

 

[iwire]

Randy:
Trailers are "outside of the building" & xfr is inside. The OP did not provide enough info

I am not following how that would change the answer? :-?

 

[Pierre C Belarge]

I would like to have a transformer located inside a school building feed two panels located in two outdoor trailers. If an enclosed circuit breaker was installed within 10' (secondary length) of the transformer on the secondary side, would it be permissable to install a wireway on the load side of the enclosed breaker and tap off two sets of conductors, one set for the first panelboard and the other set for the other panelboard (i.e. would 240.21 (B)(5) apply in this situation?).

I would like to avoid having to install a panelboard fed from the secondary of the transformer just to feed two more panelboards.

Based on the info provided, the answer to the first part of your question is yes.

You most likely will not be able to use 240.21(B)(5), that is for conductors installed outside.

 

[ElectricPersonality]

More information;

The enclosed breaker is installed to protect the secondary of the transformer.

The tap would be in a wireway on the load side of the enclosed breaker.

The transformer and enclosed breaker are located in a storage closet that is next to an exterior wall, If I don't run the feeder through any other rooms, but directly to the outside of the building out to the trailers, can I utilize 240.21 (B)(5)?

If I am reading the code correctly, by installing a breaker within 10' of the seocndary of the transformer, I don't have to then follow the transformer tap rules for the wireway where the tap is located, that is downstream of the secondary breaker. The feeder tap rules would apply in this situation?