Grounding between bus bars in a Cutler-Hammer main panel

[Kenton H. Shepard, CMI]

200 amp Cutler-Hammer main service panel.
The neutral bus bar was bonded to the upper grounding bus bar which was bonded to the box by a strap... but not connected to the lower grounding bus bar (except by the metal box).

The lower grounding bus bar had a grounding electrode that disappeared down the service entrance, hopefully to a driven rod or equal somewhere.

Shouldn't the lower grounding bus bar which was connected to the grounding electrode have been connected to the upper grounding bus bar by something more than the metal box? Like a #4 copper wire?

[Jeffrey R. Pope]

This is a common method and is fairly standard.

This type of panel can be used as a load side panel (sub panel) by removing the bonding straps from the neutral bus bars.

[Kenton H. Shepard, CMI]

Thanks Jeff.

[Greg Fretwell]

It is legal to use the "screwed to the can" busbar for the grounds but don't put the neutrals there, even in the service disconnect enclosure, unless there is a 250.66 jumper to the bar where the neutral from the utility resides.
You can probably get a code fight going but there is ample reason to say no.
Personally I like to loop a #4 through all the supplimental bus bars and back to the neutral bar on a service panel before I start loading wire in there.
You probably have a piece you cut off the GEC anyway.