250.148

[hillbilly]

If I install a new Main breaker panel and use the existing breaker panel enclosure as a junction box to splice the home runs.....

....do I have to....

Bond every equipment grounding conductor inside the junction box (old panel) to the enclosure?

or

Splice the associated grounding conductors together (individually) and bond the junction box (with a seperate conductor) to the main panel?

or

Splice the associated equipment grounding conductors together (individually) and bond the largest (home run) equipment grounding conductor to the junction box enclosure?

or

choose either one?

I've always installed a (bonded) grounding bar (or used the existing one) in the junction box to splice the equipment grounds. This means that all of them are bonded together and to the metal enclosure.

I've always thought that it is required to do so...or used to be anyway, now I'm not so sure.

Any thoughts?

steve

 

[Dennis Alwon]

I think all the grounds need to be bonded to the enclosure. A ground bar is perfect for that.

 

[Twodollar]

Bond every equipment grounding conductor inside the junction box (old panel) to the enclosure?

Isn't this the state you find the old panel in?

Additional ground bus bars can be purchased and electrically connected when the original is full. This seems like your situation except the new ground bus bar is in the new panel.

 

[LarryFine]

You can join all of the old EGC's to a single new EGC sized for the largest circuit, and bond the enclosure to that conductor.