Pigtail from ground on receptacle to box or not?

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ritelec

ritelec

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Jersey
I've been under the understanding that a receptacle in a 1900 box needed a bond jumper from the receptacle to the box so that the receptacle was still grounded with the cover removed.

Is this true or a wives tale.

Thank you
 
If the cover is dimpled at the corners (like below) no bonding jumper required because the cover has been tested and listed for grounding.

5AA31_AS01
 
Thank you.

Is a cover like that and any 4" box considered "listed"

Or would it/they have to be "marked" as listed and as an assembly. ?? (250.146A)
 
You would comply with this part of 250.156(A):

A listed exposed work cover shall be permitted to be the grounding
and bonding means when (1) the device is attached to the
cover with at least two fasteners that are permanent (such
as a rivet) or have a thread locking or screw or nut locking
means and (2) when the cover mounting holes are located
on a flat non-raised portion of the cover.
Click to expand...
 
Ok. Thank you.

I remember that they needed to have the pigtail Maybe that was before the covers changed design to two nuts and screws and not the single center screw.

I then heard that now switches need the jumper. I haven't applied that to my wiring methods when installing switches in 1900 boxes, but is that true or not ?
 
ritelec said:
Ok. Thank you.

I remember that they needed to have the pigtail Maybe that was before the covers changed design to two nuts and screws and not the single center screw.

I then heard that now switches need the jumper. I haven't applied that to my wiring methods when installing switches in 1900 boxes, but is that true or not ?
Click to expand...
Yes, did have to have a pigtail back before 2005 I think.

No, switches don't need a pigtail .
 
I think it would require a jumper but let me ask.

A 240 v receptacle where the screws go through the cover into the yoke of the device.

Not a screw with nut with lock washer.
 
ritelec said:
I think it would require a jumper but let me ask.

A 240 v receptacle where the screws go through the cover into the yoke of the device.

Not a screw with nut with lock washer.
Click to expand...

Wouldn't that still comply with 250.156(A)?
 
I don't think so??

It's screwing into the yoke like the yoke of a switch.

I don't see the thread locking or screw or nut locking means as in that article ??? As the hardware that the duplex cover comes with. Speaking of. I don't think a single receptacle 120 v comes with that locking hardware either.
 
Coming from resi, we pigtailed a ground to every device in a box...plastic box. I assumed this was to ground the metal parts of a device..
If a device is attached to a metal cover , when the cover is installed then all metal parts are grounded, but if the cover is removed they are no longer grounded...
How does it apply to one and not the other?
id think the risk of shock is greater with the metal cover,,I have removed a cover and the wire on the device come loose and arc the cover..
 
electricalist said:
Coming from resi, we pigtailed a ground to every device in a box...plastic box. I assumed this was to ground the metal parts of a device..
If a device is attached to a metal cover , when the cover is installed then all metal parts are grounded, but if the cover is removed they are no longer grounded...
How does it apply to one and not the other?
id think the risk of shock is greater with the metal cover,,I have removed a cover and the wire on the device come loose and arc the cover..
Click to expand...

Yes, the removal of the cover means the device is no longer grounded/bonded, but this is no different than the removal of a device using an approved metallic raceway as the EGC.

The assumption is that the circuit is turned off before removal off the device or cover.
 
ritelec said:
...
I remember that they needed to have the pigtail Maybe that was before the covers changed design to two nuts and screws and not the single center screw. ...
Click to expand...
I was the submitter of proposals that lead to that rule, and it had nothing to do with grounding. It only addressed the fact that the single screw often became loose letting the receptacle move when a plug was inserted or removed. In many cases it would move enough to let the partially inserted hot prong of the plug to be in contact with both hot side of the receptacle and the metal cover resulting in arcs. However there is no question that the two screw connection of the receptacle to the raised cover improved both the mechanical and the electrical connections between the receptacle yoke and the cover.
 
Not to mention before the requirement to bolt the receptacle to the cover with at least two screws came about, you used to see many of the cheap grade duplex receptacles that just couldn't hold up with that center screw being the only support. Spec grade or better receptacles typically held up just fine being supported by center screw only.

I believe when the two screw requirement cam out there was exception allowing the center screw support only if the device was listed for it.
 
The assumption is that the circuit is turned off before removal off the device or cover

I thought this might be the reasoning,,,,then in resi a ground to the device should be un necessary.
 
electricalist said:
The assumption is that the circuit is turned off before removal off the device or cover

I thought this might be the reasoning,,,,then in resi a ground to the device should be un necessary.
Click to expand...

I got this one fellas.
Electricalist think your statement through.
The device needs to be ground wherever its at resi or com.
How would the device get grounded in a plastic box unless they were ran to the device.
Jeeeez maybe he understands that.:thumbsup:
 
electricalist said:
I got this one fellas.
Electricalist think your statement through.
The device needs to be ground wherever its at resi or com.
How would the device get grounded in a plastic box unless they were ran to the device.
Jeeeez maybe he understands that.:thumbsup:
Click to expand...
It saves so much time for the rest of us when you handle the arguments against yourself too!
:)
Thanks.
 
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