250.92

[augie47]

I have what I guess is a dumb question (not the 1st). 250.92(B)4 lists the methods of bonding service raceways.
The last sentance of 250.92 states "standard locknuts or bushings shall not be the sole means,,,,,,,,," and for that reason I have always used grounding locknuts or ground bushing when using EMT on service conduits (except into hubs).
Does a standard compression EMT connector qualify as one of the methods listed ? (are they threadlesss connectors???,etc)

(I'm unsure as to what hey refer to as "threadless cionnectors" in this section)

 

[cadpoint]

"standard locknuts or bushings shall not be the sole means and for that reason I have always used grounding locknuts or ground bushing when using EMT on service conduits (except into hubs).

You forgot the first part of the paragraph, you need a Bonding device if a Connector and boss goes through and concentric and eccentric knockouts and there only required (250.97) when over 250 volts to ground, (which points right back 250.92(B),
Except for 250.92(B)(1).
A compression connector is to EMT what a Threadless is to Rigid conduit, theres a band that tightens into each conduit as its made Fast.
Thread less is the Same as a compression fitting, just used for different types of conduits.

and for that reason I have always used grounding locknuts or ground bushing when using EMT on service conduits (except into hubs).

Stay away from 250 volts to ground, stay away from concentric and eccentric’s, bonding bushing not required.

 

[augie47]

locknut

locknut

system is 480/277.....service conduits....no concentric or ecentric.....however, I'm still unsure due to the last sentence.."standard locknuts ..sahll not be the sole means for the bonding..."
since it's service 250.92(B) would apply....
The emt connector has a "standard locknut" but it would seem to me that a grounding locknut should be used in this sitaution.

 

[infinity]

The emt connector has a "standard locknut" but it would seem to me that a grounding locknut should be used in this sitaution.

You would need a bonding locknut, bonding wedge or bonding bushing. You cannot rely on the standard locknut for service conduit bonding. Also the conduit is only required to be bonded on one end.