Conduit grounding

[Alexis]

Hello!
I'm having an issue with my inspector and I'm trying to find out if he may be wrong..
I have an NM feeder between main panel and sub panel with short piece of EMT conduit to and from a crawl space.

In order to have each of these pieces grounded he is telling me that:
1. Chase nipple that goes in LB does not ground the conduit.
2. Ground busing without lock nut is not rated for grounding.
3. Lock nut alone (even without leftover concentric rings) is not rated to ground EMT. He said that lock nut is for mechanical connection but not grounding..?

I will include 3 refference photos plus photo of the piece that transitions in NM (NM connector is present)

Any advice/refferece would be greatly appreciated!

Also wanted to check: in your area when doing main panel grounding by the main water - is jumper over main water regulator required? Is it even a code?

Thank you!

 

[don_resqcapt19]

Not sure about 1, but he is 100% wrong on 2 and 3. The busing with the bonding jumper will bond the conduit. All EMT connectors are suitable as part of the fault clearing path per the product listing standard.

 

[Dsg319]

Wouldn’t photos 2/3 be compliant with just standard lock nut?

 

[infinity]

Wouldn’t photos 2/3 be compliant with just standard lock nut?

Yes.

1. Chase nipple that goes in LB does not ground the conduit.

I agree even though this is done everyday.

2. Ground busing without lock nut is not rated for grounding.

I agree, the locknut is required because the bushing is not designed to cut into the painted surface like a locknut is.

3. Lock nut alone (even without leftover concentric rings) is not rated to ground EMT. He said that lock nut is for mechanical connection but not grounding..?

The locknut is all that's required even with concentric or eccentric KO's because the voltage is less than 250 volts to ground.

 

[Joe Villani]

For issue #1 is the raceway even required to be grounded? Wouldn't 250.86 Exp 2 apply here?