Outlet w/box deep in sheetrock w/ EMT and metal boxes - Jumper box to outlet needed?

MPdesign

Member
Location
USA
So, I have a building with EMT raceway to metal boxes in the wall.
The boxes are far in the wall so that the outlet strap cannot be used to ground the outlet to the box.
The box is grounded by the raceway.
The outlet is grounded by a conductor to the ground screw.
There are no jumpers from the ground to the box.
It is my understanding that the outlet has to be bonded to the box.
Is that correct - or am I mistaken?
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
If EMT is the only EGC then the only way your receptacle is grounded is by bonding to the box that if correctly installed is bonded to the EMT. If the mechanical bond via the strap is not possible due to the depth of the box recess then a wire bonding jumper needs to be installed between the receptacle and the box to ground the receptacle.
 

MPdesign

Member
Location
USA
The outlet is grounded by a conductor to the device ground screw only. This grounding conductor is not connected to the box.
Is a wire bonding jumper from the outlet to box required?
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
The outlet is grounded by a conductor to the device ground screw only. This grounding conductor is not connected to the box.
Is a wire bonding jumper from the outlet to box required?
This is not as indicated in initial post where you stated "The box is grounded by the raceway."
If ground conductor is present it would appear the raceway is not being relied on as an EGC, the box would be bonded from EGC first then to the receptacle, or pigtail to both box and receptacle from the wire EGC is another way. Unless it is an isolated ground receptacle.
 

MPdesign

Member
Location
USA
Thank you for your insight!
That is what I thought, but I have been away from it for a long time and wanted to recheck.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
The outlet is grounded by a conductor to the device ground screw only. This grounding conductor is not connected to the box.

You are saying that the outlet green ground screw has a wire on it that is not connected to anything? Yes, connect it to the box with a ground screw. Whoever installed it originally figured that the screws holding the outlet to the box were sufficient. I would not rely on them.

-Hal
 
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