Ground bushings

[Crabcakes&football]

These always throw me off. MDP feeding transformer with flex then feeding my 120v panel with flex. I made my own knockouts and have equipment ground with my flex. Do I need a grounding bushing?

 

[Dsg319]

 

[Dsg319]

These always throw me off. MDP feeding transformer with flex then feeding my 120v panel with flex. I made my own knockouts and have equipment ground with my flex. Do I need a grounding bushing?

Are you asking for low voltage side or high voltage side? Assuming your using metallic flex?

 

[Crabcakes&football]

Yes metal and low voltage side

 

[augie47]

I don't see the need for a bonding bushing.
You have no concentric or concentric to worry about and on the HV side 250.97 allows flex connectors:
Fittings with shoulders that seat firmly against the box or cabinet, such as electrical metallic tubing connectors,flexible metal conduit connectors, and cable connectors, with one locknut on the inside of boxes and cabinets

In addition, the flex can not be a grounding conductor for those currents so bond bushings would seem a waste.

 

[Crabcakes&football]

I've asked 3 different journeymen and each gave me a different answer. One reason I'm on here. I didn't think I needed any. But each guy said something different.

 

[Dsg319]

I've asked 3 different journeymen and each gave me a different answer. One reason I'm on here. I didn't think I needed any. But each guy said something different.

As I’ve seen it said before on here, flexible metal conduit can only be used as an EGC on circuits with 20amp OCPD. Though idk the code ref for that, could be manufacture note, so regardless would be pretty much a waste of a bond bushing. (As long as your using listed connections FMC connectors upon entering the panel.)

 

[infinity]

Yes metal and low voltage side

Not required on either side (high or low) if there are no concentric or eccentric KO's. I see guys still wasting money installing these.

 

[Crabcakes&football]

Thats what I thought too,one co-worker said I needed on and the other I needed it on both sides of the flex. Seems like nobody knows hahaha

 

[infinity]

Thats what I thought too,one co-worker said I needed on and the other I needed it on both sides of the flex. Seems like nobody knows hahaha

We know. Ask for a code reference.

 

[Crabcakes&football]

Seems like it's a personal preference to inspectors too. I failed an inspection last year cause I didn't have a grounding bushing. Same setup im doing now. Different inspector this time.

 

[infinity]

If the inspectors are calling something out as a violation then a code reference needs to be given. Same goes for the code guru co-workers. They won't find one for this.

 

[Crabcakes&football]

Hahaha ill find out Tuesday. Thanks for your input.

 

[BillyMac59]

Curious how three different electricians gave you three different answers to a "yes/no" question...

 

[Crabcakes&football]

Technically they all Said yes but different variations