Is the bond lost from MC to an LB to EMT?

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PowerMan2020

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6-2 MC from the panel to the back of an LB.
Unsheathed the MC from the LB and then EMT from the LB directly into a plastic Tesla Wall connector.
A simple run (MC to LB to EMT).
Is this not an acceptable bond? There is an inspector in the area that is failing jobs because he wants a JBox and not an LB as the point of transfer....says the LB is not able to carry a proper bond like the JBox is.
I was under the impression that MC is actually conduit and so is an LB (a conduit body) and EMT is also obviously conduit.
Thanks for any comments and code interpretation.
 
1. Welcome to the forum.

2. Where in VA are you?

3. I can see his point. What grounds the LB and the EMT? The MC sheath itself does not qualify as an EGC.

Can you land the EMT in a box where you can hit a grounding screw, even if only a handy-box and blank?
 
Glad to be here thanks. From Northern VA (Tysons).
Sure, I can use a box and then pass the ground through a grounding lug in the box. It is simply an extra step and not quite as sleek-looking as an LB.
Alternatively, I suppose I could put a grounding screw and lug in the back of the LB and pass the ground through that. I use an oversized LB (1") to make sure there is the space/volume for it.
 
PowerMan2020 said:
Glad to be here thanks. From Northern VA (Tysons).
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I used to live in N. Springfield, just inside the beltway off Braddock Rd.

Sure, I can use a box and then pass the ground through a grounding lug in the box. It is simply an extra step and not quite as sleek-looking as an LB.
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I meant at the other end, at the Tesla Wall.

Alternatively, I suppose I could put a grounding screw and lug in the back of the LB and pass the ground through that. I use an oversized LB (1") to make sure there is the space/volume for it.
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If the inspector considers that acceptable. You'd have to tap the LB.


Hey, it just hit me: put a bonding bushing on the EMT connector inside the plastic housing of the Wall.
 
Dennis Alwon said:
Do you have room to tap a ground in the LB?
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Lots of room in an 1" LB with only #6-2 wire in there. Requires: a quick drilling/tapping for an lay-in ground lung and screw and the ground wire be stripped. Harder to do if the wire is already ran.
The bond bushing at the end would be my choice.
 
AKElectrician said:
Is the LB rated for Mc or Romex connectors?
Just cause it fits don’t make it legal, sprinkler pipe fits emt connectors...
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For the love of all things, who do we have to bombard with emails to get this ridiculous, stupid, absurd listing issue fixed?! Tapered VS straight threads are fine. They work fine. It's not that they are somehow "unsafe," it's just that no one's (UL) has actually tested the combo to "prove" what electricians have known for years.

Can we, as an industry, please settle this and put it behind us?


SceneryDriver
 
PowerMan2020 said:
6-2 MC from the panel to the back of an LB.
Unsheathed the MC from the LB and then EMT from the LB directly into a plastic Tesla Wall connector.
A simple run (MC to LB to EMT).
Is this not an acceptable bond?
Click to expand...
My question would be why is the MC Sheathing to LB to Emt a bond concern, as long as the system has an uncut grounding conductor which originated at a grounding bar and ends at a grounding lug ... the rest is simply protection for the conductors .. yes , or is there really some sort of induction-harmonic concern ..
 
The only violation I've been challenged on is when going from MC or NM cable to an emt application is that the wiring of a fixed cable has no markings allowing for the bored inspector to say hey .. I don't see any AWG markings every 12"
 
Another C10 said:
My question would be why is the MC Sheathing to LB to Emt a bond concern, as long as the system has an uncut grounding conductor which originated at a grounding bar and ends at a grounding lug ... the rest is simply protection for the conductors .. yes , or is there really some sort of induction-harmonic concern ..
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The load end of the MC run has no place to land the EGC; there is no grounding lug. The question is about how to accomplish such a termination, which is where the bonding bushing or affix a lug ideas come into play.
 
LarryFine said:
Hey, it just hit me: put a bonding bushing on the EMT connector inside the plastic housing of the Wall.
Click to expand...
Last bicker ... no offence but does anyone else see the point of bonding a metal connector to a plastic enclosure, is there really no grounding termination of the telsa wall equipment
 
The mc cable has an egc. The Tesla charger certainly has a terminal for landing the egc, so there is no compromise on the bonding of the charger itself.

The issue is the bonding of the LB itself. It isn't considered bonded by the mc sheath, nor by the EMT going into the plastic enclosure. It doesn't contain a splice so one might question if it needs bonding.

LarryFine's solution might cover the issue, bonding the LB via the EMT to the egc in the charger.

Jon
 
winnie said:
The mc cable has an egc. The Tesla charger certainly has a terminal for landing the egc, so there is no compromise on the bonding of the charger itself.

The issue is the bonding of the LB itself. It isn't considered bonded by the mc sheath, nor by the EMT going into the plastic enclosure. It doesn't contain a splice so one might question if it needs bonding.

LarryFine's solution might cover the issue, bonding the LB via the EMT to the egc in the charger.
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"Excuse me, sir. Seeing as how the V.P. is such a V.I.P., shouldn't we keep the P.C. on the Q.T.? 'Cause if it leaks to the V.C. he could end up M.I.A., and then we'd all be put on K.P." ~ Robin Williams as Adrian Cronauer in Good Morning, Vietnam
 
SceneryDriver said:
For the love of all things, who do we have to bombard with emails to get this ridiculous, stupid, absurd listing issue fixed?! Tapered VS straight threads are fine. They work fine. It's not that they are somehow "unsafe," it's just that no one's (UL) has actually tested the combo to "prove" what electricians have known for years.

Can we, as an industry, please settle this and put it behind us?


SceneryDriver
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Do your self a favor and try to use RMC in die cast, then in a form 7 Condulet and tell me which makes a better mechanical connection.

Again with EMT fittings.

Ever have a cheap lock nut that won’t fit a RMC nipple?
It’s cause it’s a fitting lock nut meant for connectors. Fittings for emt connectors are not a tapered thread so they need smaller lock rings. So other lock rings seem loose on connectors, those are for tapered threads.

That’s how I understand the issue, and could be wrong.
 
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