[sdRick]

I have a strange situation going on in my bathroom device box where I want to install a GFCI. The house was built in '71. The box has 1 outlet and a double switch. One side for the light and one for the fan. Turns out there are 5 3-wire conduits coming in there. I believe that:

• 1 is power directly from the circuit breaker.
• 1 is leaving to go to the fan
• 1 is leaving to go to the light
• 1 is going to an attic light and then onto a bed light
• 1 is going to kitchen lights

So it's way to crowded in there. I then decided to put a junction box in the attic for the power,attic,and kitchen lights, then just one power down to the bathroom. However upon further inspection i don't know what is going on with the grounds. Each of the 5 grounds that enter the box immediately do a u-turn and go back up and I think to the left. 1 ground comes back in and was hooked to the outlet. The double switch did not have a ground, i changed that.

I am now skeptical about removing the lines and putting the junction in the attic because of the weird grounding situation. But I can't fit a GFCI in the current overloaded box so I think I need to do it.

Does anyone have any thoughts on what might be going on with the grounds?

Thank you
Rick

 

[Jim Port]

A picture might help us understand better.

 

[sdRick]

You got it, I'll try to take one tonight.

 

[MrElectricianTV]

I have a strange situation going on in my bathroom device box where I want to install a GFCI. The house was built in '71. The box has 1 outlet and a double switch. One side for the light and one for the fan. Turns out there are 5 3-wire conduits coming in there. I believe that:

• 1 is power directly from the circuit breaker.
• 1 is leaving to go to the fan
• 1 is leaving to go to the light
• 1 is going to an attic light and then onto a bed light
• 1 is going to kitchen lights

So it's way to crowded in there. I then decided to put a junction box in the attic for the power,attic,and kitchen lights, then just one power down to the bathroom. However upon further inspection i don't know what is going on with the grounds. Each of the 5 grounds that enter the box immediately do a u-turn and go back up and I think to the left. 1 ground comes back in and was hooked to the outlet. The double switch did not have a ground, i changed that.

I am now skeptical about removing the lines and putting the junction in the attic because of the weird grounding situation. But I can't fit a GFCI in the current overloaded box so I think I need to do it.

Does anyone have any thoughts on what might be going on with the grounds?

Thank you
Rick

I have seen that set up with the grounds many times. Usually it is in houses built in the 1950's and early 60's. The grounds are terminated outside the box. Most common with that installation is all of the ground wires are crimped in a copper lug and then attached on the outside of the box. The most common attachment point is one of the screws that hold the box ears in place. If you are able to see past the edge of the top of the box into the wall you may see the lug. In some cases I was able to cut the wall open ever so slightly and insert a tiny screwdriver sideways into the screw slot to loosen the screw enough to free the lug. Then I cut the lug off and use needle nose pliers to separate the grounds. I can then pull the grounds back in the box by loosening the cable clamps. It is a slow process if you don't want to damage the wall. One box I found several months ago had the lug on the back of the box. I was lucky that I needed to cut a hole in the wall behind that box anyway.

I am surprised to hear of that ground arrangement on a house built in 1971. Maybe an old timer wired it or a DIYer who mimicked something he saw.

 

[rjniles]

Google "Boston back wrap." It was an old method to wrap the ground back around the cable and ground it to the box under the cable clamp. It was forbidden starting in the early 70s but I have seen it used later than that.

 

[sdRick]

Thanks for the input.
I understand what you are explaining. Would it make a difference if the device box is not metal? Would you still assume the same 'back wrap' method?
thanks again.

 

[rjniles]

Boston back wrap was only used with metal boxes.

 

[MrElectricianTV]

Google "Boston back wrap." It was an old method to wrap the ground back around the cable and ground it to the box under the cable clamp. It was forbidden starting in the early 70s but I have seen it used later than that.

I have seen a few of those installations. I did not know that there was a name for that method. Thanks for the history lesson RJ.

 

[sdRick]

You were right guys. The grounds were terminated outside the box. The grounds weren't connected to anything on the box or the wall just crimped together outside the box. I needed to replace the old box anyway so I tore it apart piece by piece to get at all the wires without having to cut any of them. It was an old fiberglass kind of box so it tore apart pretty easily.
Thanks for your help.