DIY Home Improvement Forum banner

1 - 20 of 21 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter #1
How do you guys do your ground? I've seen this a few times with metal boxes. They say you can ground on the wire nuts like that and then when the metal outlet tabs and screws are screwed into the metal box that it grounds itself without using the ground screw on the outlet and in the box. What are the pros/cons of this?

 

·
Registered
Joined
·
2 Posts
In side the box is a grounding screw, that is where it should be grounded both to the box and the device. The way it is now if by some chance the ground becomes hot it could melt the casing and start a toxic fire in the wall.
 

·
Registered
Joined
·
45 Posts
Doesn't seem like the most secure connection for a ground. Should make a pigtail from the box, pigtail to outlet ground screw, and connect those to incoming ground(s)
 

·
Registered
Joined
·
18 Posts
Discussion Starter #4
In side the box is a grounding screw, that is where it should be grounded both to the box and the device. The way it is now if by some chance the ground becomes hot it could melt the casing and start a toxic fire in the wall.
Wouldn't it melt and cause a fire either way if the ground became hot?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #6
it won't melt.... the job of the grounding conductor is to clear a fault, in order to do this, it MUST become energized...

Why people throw out comments at will is beyond me.
So how wrong/dangerous is the picture?

It seems to be ok as long as you don't remove the outlets because then the ground would be gone?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #9
The grounding install is all wrong, for whatever reason, that technique was used early on, but the grounding conductor must be made up inside the box, the metal box and device all bonded together.
How long ago was that technique used?
 

·
Super Moderator
Joined
·
13,978 Posts
Probably 40 years ago or more.

The sheath must extend into the box at least 1/4". All grounds need to be connected together and to the box and device.
 

·
Civil Engineer
Joined
·
5,832 Posts
Yes it is sloppy, but let's back up for a second. My entire house was grounded in a similar manner. House was built in 1959, I a guessing that the technique of wrapping wire around a screw on the outside of a metal box was pretty typical in 1959. And the technique likely violates current NEC requirements, since the grounding wire is apparently supposed to be connected to a green grounding screw inside the box. But the technique certainly works electrically, since the copper grounding wire is mechanically connected to the box.

Assuming the outlet grounding wire is connected to a grounding screw inside the box via a pigtail, the system is electrically grounded. I would class this as a technical violation of NEC, and if the wire was installed some years ago, it may have been compliant with regulations at the time, in which case it may be grandfathered. Is it worth fixing? Probably, but does not look like a really high priority. If the outlet is ungrounded, that is a more serious problem, but you can't tell from the photo.
 

·
E2 Electrician
Joined
·
5,655 Posts
Yes it is sloppy, but let's back up for a second. My entire house was grounded in a similar manner. House was built in 1959, I a guessing that the technique of wrapping wire around a screw on the outside of a metal box was pretty typical in 1959. And the technique likely violates current NEC requirements, since the grounding wire is apparently supposed to be connected to a green grounding screw inside the box. But the technique certainly works electrically, since the copper grounding wire is mechanically connected to the box.

Assuming the outlet grounding wire is connected to a grounding screw inside the box via a pigtail, the system is electrically grounded. I would class this as a technical violation of NEC, and if the wire was installed some years ago, it may have been compliant with regulations at the time, in which case it may be grandfathered. Is it worth fixing? Probably, but does not look like a really high priority. If the outlet is ungrounded, that is a more serious problem, but you can't tell from the photo.
It's a hacked installation, and the yellow NM shows it's not an old installation. And ground screw does not have to be green.
 

·
A "Handy Husband"
Joined
·
12,363 Posts
A long time ago back when NM had a cloth jacket and it was done much nicer than in your picture, thats a new install, but some hack did the work.
It was done back in the 50's through the 60's (when grounded cables became a requirement), primarily in the Northeast. And hence the name "Boston Back wrap". But even then the sheathe was brought into the box and the ground was wrapped tightly back around the cable and secured under the clamp. Even if done correctly it is no longer compliant.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #16
I just want to prove a point to someone. I think we agree it isn't up to code and not the proper way, but why is it not ok? What is the problem with it? There are probably millions of houses grounded this way. Ignore that the wire should be further in the box, that's a given.
 

·
A "Handy Husband"
Joined
·
12,363 Posts
I just want to prove a point to someone. I think we agree it isn't up to code and not the proper way, but why is it not ok? What is the problem with it? There are probably millions of houses grounded this way. Ignore that the wire should be further in the box, that's a given.
The problem is it does not meet code. What are you trying to prove?
 

·
E2 Electrician
Joined
·
5,655 Posts
I just want to prove a point to someone. I think we agree it isn't up to code and not the proper way, but why is it not ok? What is the problem with it? There are probably millions of houses grounded this way. Ignore that the wire should be further in the box, that's a given.
Why do you think it's okay? The ground wire is squeezed between the connector, no way is this going to be a low resistance path for a ground fault.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #19
Why do you think it's okay? The ground wire is squeezed between the connector, no way is this going to be a low resistance path for a ground fault.
When did I say it was ok?

I'm asking for facts as to why it is not ok, not "because it isn't code".

How many millions of houses do you think are wired this way?

You're an all knowing professional that does everything perfect and up to code so explain it.
 
1 - 20 of 21 Posts
Top