How to properly connect grounding wires...

[mpire]

Ok, so I just finished reading the horror story thread about poor installation of wiring etc. So now I am wondering if the ground wires are correct in a couple places in my house.

In several spots the power wires have nuts on them, but the ground wires are just twisted together. In the attic there may be 5 or 6 ground wires twisted together.

I know that every junction has to have a box and a cover, but I am not so sure about the proper way to connect grounding wires.

 

[willysrule]

I'll start by saying I'm not a professional electrician but I know enough to be dangerous... however my old man is a Journeyman Electrician...so I asked him his thoughts on this...

Check your local code; some are more stringent than what the NEC calls for...

Some inspectors actually accept this for ground wires in older construction. It is NOT code legal though in most people’s opinion, because there is nothing “securing” the wires together, so if one or more of those wires come undone or are not making good contact you could have part of the circuit without a ground. If you are worried about finding or buying wire nuts big enough to hold that many wires you can always use the small screw lugs, just to be sure the wrap is held together securely…

In his professional opinion (and how he ALWAYS does it), a crimp, lug or wire nut is required.

If you can understand what your reading you can google NEC 250.148 & 110.14(B) for the part of the code he says this falls under…

 

[Aceman]

Twisting alone doesn't cut it.

You need a crimp, wirenut, etc mechanically holding the connection together.

Often times, it's twisted several times all the way back into the box, so I know adding one wirenut to the end of the connection realistically isn't going to make it a whole lot safer than it already is. But, I still do it when I come across connections like that...

 

[slimpickins]

Good response from Willysrule.

I agree. The ground wires need to have a wire nut or crimp nut on them. Just gimballing the wires together is asking for trouble. Willysrule is also right that you have to follow your local code. In Canada, the code varies from province to province and in the US it probably varies from state to state. You NEED to follow your local code. The electrical code is there for your safety and you should follow it.

I'm not an electrician either, but have done a lot of wiring all my life and I could probably write the code test.

To elaborate on this a bit - grounding may seem like a simple thing but there is a lot of intricate rules to grounding (and for good reason).

For example - here's a grounding rule I see broken all the time by "handymen": If you are adding wiring to an existing older system where the lomex/romex cable doesn't have a ground wire and the outlets are not grounded, then, in my area, you MUST cut the ground wire off on the new wiring and you CANNOT ground or bond any of the receptacles together unless you ground the entire circuit. The reason for this is that if you bond the receptacles together without grounding the entire circuit, a faulty device that has a short to ground could result in a hot chassis on another outlet. I have seen this error with grounding way too many times.

In short (no pun intended) you need to be really careful with grounding. Make sure you know and understand what you're doing or call a reputable professional .... and make sure he knows what he's doing.

 

[rabidsquirrel]

Everyone is forgetting that in nearly every home more than 20 years old that's just the way it was done, no wire nuts. There's no need to panic and go around slapping wirenuts on the splices. Whenever you dig into a box, correct it as you see it.

 

[mpire]

My home was built in 2001. So now you have me thinking I need to double check stuff.

I need to figure out how to crimp these things together then. I am already worried about too many wires. Instead of chaining the lights together in a row, they appear to have done them in a "star" pattern off of one box.

 

[rabidsquirrel]

Just throw a wire nut on it if you're that concerned. Unless you have the stuff to crimp it (and it sounds like don't), it's easier to put a wire nut on it.

 

[malibu101]

I never leave home without this type of wirenut, especially for new work.
http://compare.ebay.com/like/190507...fad9d12&itemid=190507803842&ff4=263602_309572

 

[willysrule]

Everyone is forgetting that in nearly every home more than 20 years old that's just the way it was done, no wire nuts. There's no need to panic and go around slapping wirenuts on the splices. Whenever you dig into a box, correct it as you see it.

that is why my old man said some inspectors accept this for ground wires in older construction. I would have to agree, I wouldn't stress about it, just correct them as you find them...

 

[tfi racing]

If you are adding wiring to an existing older system where the lomex/romex cable doesn't have a ground wire and the outlets are not grounded, then, in my area, you MUST cut the ground wire off on the new wiring and you CANNOT ground or bond any of the receptacles together unless you ground the entire circuit.

Interesting.I don't have my CEC handy,could you please post the rule so I can have a look at it tomorrow?This situation does call for GFCI protection,but I don't recall seeing a requirement,or it being permissable to "cut" off the bonding conductor...As always,your local rules may vary...

 

[kbs2244]

The problem is that your can get quite a bundle of wires to tie together.
I sometimes use a wire tie to keep them from pulling apart.
And it is hard to find wire nuts for more than 3 wires.
I have even resorted to jumpering if I have more wires than will fit in on nut.

 

[rabidsquirrel]

And it is hard to find wire nuts for more than 3 wires.

Not really, you just need bigger nuts. *Snickers*

http://www.3m.com/intl/ph/electrocomm/eletrical/connectors.htm

The chart is a little hard to read, but you can fit 5 #12s in a Red/Yellow.

 

[mpire]

I can't wait to take a picture of this junction box so you can tell me how much of an idiot the previous homeowner was.

 

[theoldwizard1]

Everyone is forgetting that in nearly every home more than 20 years old that's just the way it was done, no wire nuts. There's no need to panic and go around slapping wirenuts on the splices. Whenever you dig into a box, correct it as you see it.

+1 !

It was accepted practice for many years. The key is are the grounds "securely" attached to one another (multiple twists).

I have seen it in many houses from the 40s-70s. If it looks secure, I just leave it alone.

Next, folks will be adding 4-6" of bare copper spliced with a green wire nut to the clipped ground wire unscrewed from the back clamp of a metal box so they can directly connect it to the ground screw.

Get a life ! They had inspectors back then (well, most of the time) and you don't see every 50-60 year old house bursting into flames from bad wiring. I would be more afraid of all of the house with knob and tube that are still around !