Irc jumper but not for device to metal box

[wyreman]

I'm trying to explain why you need to have a jumper wire for a device on an IRC cover but not for just a device Flushmounted to a finish metal box.

I keep coming back to "just because"


In belief, man can do anything

 

[mopowr steve]

Are you referring to a RS (raised surface cover) in which a ground jumping wire is not required as long as the mounting hole portion of the cover has been indented so to make contact with box.

 

[kwired]

This is a topic where I can see there being local codes that differ from NEC.

Per NEC the flush device may or may not need a bonding jumper - devices that have a "self grounding design" wouldn't need an additional bonding jumper when mounted to a grounded metal enclosure, without such "self grounding design" they still wouldn't need to if the device is making secure metal to metal contact to a grounded metal enclosure, but if not self grounding design and the device is "floating" so to speak - it will need a bonding jumper to it.

Surface raised covers only need a bonding jumper if not a type with the mentioned indented corners that ensure good metal to metal contact between the grounded metal box and metal raised cover.

 

[wyreman]

Oh yeah those raised cover w the dimples came in about maybe 5/6 years ago and there's a new rule for them! Thanks guys

I'll doublecheck with my inspector

Thx!


In belief, man can do anything

 

[kwired]

Oh yeah those raised cover w the dimples came in about maybe 5/6 years ago and there's a new rule for them! Thanks guys

I'll doublecheck with my inspector

Thx!


In belief, man can do anything

The covers that qualify have been around a long time, code finally changed to allow them without a bonding jumper more recently.

 

[Little Bill]

People get this confused about jumpers, both with the raised covers with the flat spots for mounting and any other metal box. It is/was thought that you brought the EGC to the device (recep or switch) and then jumper to the box if needed. That is wrong, you have to land the EGC in the box then either it needs a jumper to the device or not depending on the circumstances.

Simply put, EGC to the box then if jumper is needed it goes to device, not the other way around.

 

[kwired]

People get this confused about jumpers, both with the raised covers with the flat spots for mounting and any other metal box. It is/was thought that you brought the EGC to the device (recep or switch) and then jumper to the box if needed. That is wrong, you have to land the EGC in the box then either it needs a jumper to the device or not depending on the circumstances.

Simply put, EGC to the box then if jumper is needed it goes to device, not the other way around.

Correct, always needed to make sure the box was bonded first then you may or may not need jumpers to devices, covers, etc. depending on other rules and conditions.