Tap off sub panel

[Electricalartist]

Bare with me it's been a long time. Where I work there's a 225 amp main lug subpanel fed by a main distribution. 225 amp breaker.
They want a subpanel somewhere near the facility so this panel would be nice to tap off of. Are you allowed to get power from a panel with out the main breaker in the panel?

 

[infinity]

Sure but the tap rules would apply if the conductors to the new panel are smaller than the OCPD ahead of the existing panel.

 

[LarryFine]

Sure but the tap rules would apply if the conductors to the new panel are smaller than the OCPD ahead of the existing panel.

But if you actually mean the feeder on a breaker in the sub-panel, no problem at all.

 

[electrofelon]

Generally no problem, although what you mean by, and how you make the "tap" would be nice to know. Are you thinking of just putting in a breaker or tapping off the main conductors? What size u thinkin'?

 

[infinity]

But if you actually mean the feeder on a breaker in the sub-panel, no problem at all.

I meant that the tap rules would apply because he said "tap" and made no mention of adding a breaker but who knows exactly what the OP means by "tap".

 

[Electricalartist]

Sorry I want to feed the new subpanel off a breaker.

 

[NoahsArc]

Per 215.3, 240 pt I generally applies. Pt II is by and large irrelevant other than basics that are already covered by the current subpanel.
The tap conductors downstream (in this instance not "tap" tap conductors) are protected by the CB at the point of the tap.

 

[infinity]

Sorry I want to feed the new subpanel off a breaker.

No issue. Just said the feeder conductors to the breaker size.

 

[Electricalartist]

Now how do I know the maximum size panel I can use as a sub

 

[infinity]

Now how do I know the maximum size panel I can use as a sub

You'll need to calculate what your added load is for the new panel. If you're just installing a panel for the future and their is no load then install any size panel that you want.