Bonding Metal Junction Boxes

[flip]

Does the bonding jumper used to connect the metal boxes and enclosures in a raceway, need to meet the same requirements as the equipment grounding conductor??

EX) 30 amp circuit with #10 grounding conductor. Does jumper to box need to be # 10- also??? Where in Code??

 

[bphgravity]

Re: Bonding Metal Junction Boxes

When it comes to bonding, you pretty much only have two choices for sizing. Table 250.66 for equipment on the supply side of the service and Table 250.122 for equipment on the load side of the service.

Your installation is obviously on the load side of the service and therefore will be sized per Table 250.122 as specified in Section 250.102(D). A full sized #10 will be required.

 

[flip]

Re: Bonding Metal Junction Boxes

Thanks. That is what I have always done. Question was brought up because the pre-made equipment grounding conductors with the screw already attached is only available in #12. And the truth be known, the jumper is going to carry way more than the rating of the conductor during a short circuit or ground fault. Therefore, wouldnt it make sense to allow the wires to be a minimum size. Especially since the current flow through the conductor is going to be for a split second???

 

[drwill]

Re: Bonding Metal Junction Boxes

I believe what you are talking about is only for 20amp or less receptacles or switches, outlet boxes.