Is this panel bonded or not?

I’m stumped on whether or not this panel is bonded or not. The Bond screw location diagram provided on the panel indicates that the bond location is at the bottom of the bus bar, but that screw appears to be the attachment screw for the bus panel rather than a larger bond screw that I typically see but cannot be sure. The hole just above that screw has no threads but the upper holes do. And yes it is the main service panel. Any help would be greatly appreciated?

It’s hard to tell from the photo but it appears that the hole indicated on the label for insertion of the bonding screw is empty.


If it’s not bonded any other way, it certainly isn’t bonded through the designated bonding screw.

EGC termination point?

You can see the EGC a little better in this photo. The hole above the bottom screw has no threads

The threads (if there are any) would be in the metal cabinet not the neutral bus. Usually a self tapping screw is used for the MBJ (main bonding jumper) so there would be no pre-tapped threads.

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Sure appears to be missing the designated screw that does the actual bonding.

Main distribution/main panel?
The ground termination. If both EGC terminations are secured, and the AWG is correct, the panel is grounded/bonded from what I understand.

That’s what I thought too but there are no threads inside of that hole

A service panel is a distribution or load center that contains the main disconnecting means. This is the ONLY panel where the neutral and grounds should be joined (bonded) together.

The main distribution panel (not in remote/subs) should be the only location the grounds and neutral meet, via the noted screw or jumper. May be some type of self tapper or threads on bar behind front plate we are not seeing, screw is usually in a bag in bottom of panel when new.

See bottom of page 38-39…

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Bingo. Thanks!

Instead of calling this a main panel it would be better to call it a service which would align with NEC terminology.

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Much appreciated, Jim.
Sound words of advice.
Great link.

Looks like no MBJ screw is missing

Thanks so much for the help guys!