industrial switch rack

[RowE]

I have an switch rack on an oil and gas location. The switch rack is made up of 2 pieces of 2" rigid conduit cemented in the ground with several pieces of unistrut clamped between the 2 pieces of rigid to mount the enclosures on the service is appox 1/4 to 1/2 mile away in most applications. urd is ran underground to the switch rack at the production site and stubs into a disconnect on the rack. At this point the grounded conductor is bonded to the enclosuse inside the 30A disconnect and stops there. The production unit has an electric motor on skid. An equipment grounding conductor is bonded to the motor and skid runs along the conduit underground and attaches to a ground rod at the rack and clamped to one of the 2" poles of the switch rack. Each enclosure is bolted to the strut using bolts and spring nuts. I have a problem with the strut clamps and painted enclosures that do not appear to have been strip of paint being my effective ground fault path to the grounded conductor. Is this effectively grounded?

 

[DaveTap]

I can see all kinds of potential problems here... yes its probably grounded but how effectively is debatable.
What kind of clamp did they use for EGC to the rigid conduit?
Is the uni-strut painted or galvanized?
Were star lock washers used between bolt/nuts and cabinets?

I know we're allowed to use metal conduit as our EGC when installed with locknuts (and/or ground bushings etc) to our boxes, but what about when using them as supports?
Are we even allowed to use them as supports except for some service mastheads?

Why didn't they just run the EGC into the box?

 

[RowE]

the eguipment ground conductor is connected to the rack with an approved 2" grounding pipe clamp. no star washers were used in the enclosures when mounted, unistrut is galvanized. I usally see bonding jumpers run inside or outside the raceways or enclousures for each piece of equipment monted on the rack and bonded to the grounded conductor and grounding electrode at the disconnect on the rack, but this is not the case here.