208 volt panel handle 240 volts?

[powerplay]

Is it possible to use a 208 volt rated panel for 240 volt power temporarily? I would assume the panel can handle the voltage, and in a pinch was thinking of using 2 of three phases in the panel as a temporary subpanel....if the bus can handle the voltage?

 

[mbrooke]

I would assume its ok, most panels rated 120/208Y are also rated 120/240 delta.

You can use it for single phase, keep in mind you will lose 1/3 of the phases. As long as the breakers are 120/240 rated its fine.

 

[ritelec]

I would assume its ok,

Can you check? Panel, Manufacturer? I would also assume ok...but............if it's not and something happens.........well, you know who they will come looking for.

 

[powerplay]

It's an 3 phase 200 amp Federal Pioneer panel.

I wanted to use it temporarily because the panel was already there with breakers in it. I prefer special permission in writing when installing contrary to the literal translation of the code, and will check with FPE but I speculated they wouldn't change the rating/design of the bus system (other than the extra leg) for the few extra volts from 208 to 250 volts for panels rated less than 480 volts.

Thanks again for the feeedback!

 

[Jraef]

Breaker pole spacing is the issue, and it only comes in 2 classes, 300V and 600V. So for everything 240V and down, the pole spacing might be a little tighter because it can be and they want to cram more breakers in a tighter space, but for 480V, you can't do that because of the risk of flash over between poles.

So bottom line, no problem using 240V on a 208V listed panel, at least temporarily. But if it is 3 phase service, you have an issue with the 120/240V 3 phase 4 wire issue. In a panel made specifically for 120/208V 3Ph4W, there are no restrictions on putting 1 pole breakers anywhere you want to. On a 120/240V 3Ph4W panel, some mfrs restrict you from connecting 1 pole breakers to the High leg. If you use a 208V 3Ph panel, you must be careful to not put 1 pole breakers in the High leg bus, and there will be no help from the mfr.

 

[powerplay]

So bottom line, no problem using 240V on a 208V listed panel, at least temporarily. But if it is 3 phase service, you have an issue with the 120/240V 3 phase 4 wire issue. In a panel made specifically for 120/208V 3Ph4W, there are no restrictions on putting 1 pole breakers anywhere you want to. On a 120/240V 3Ph4W panel, some mfrs restrict you from connecting 1 pole breakers to the High leg. If you use a 208V 3Ph panel, you must be careful to not put 1 pole breakers in the High leg bus, and there will be no help from the mfr.

Thanks... definetely so much to learn!

I have an single phase service that had an rotophase feeding an panel, but the 120/240 voltage in a 3Ph4W panel achieved in a delta corner ground secondary? ...can this can be metered to determine which is the high leg by metering to neutral then between phases? one leg would be a different voltage on a single pole in the case of 120/240 volts 3ph4w?

 

[powerplay]

oopppss...i suppose the 120/240 3ph4w is achieved through grounding mid point of one leg...