Two Questions about Code (NEC)

[piratius]

Hey guys!

Two really quick questions. I'm approaching the point where I need to have the inspector come out and look at my wiring, boxes, and connections at the breaker panel. I have 12/2 run through the walls for 20A service, and 14/2 up in the ceiling for lighting, and boxes along the walls and ceiling (simple version). All that's left to do is tie everything in at the panel (simple) and join the safety grounds in all the boxes.

First up - The general contractor who built the structure said that I need to pull all the safety grounds together in the box and use a ground crimp to hold them all, and that they won't approve the use of wire nuts for the safety grounds anymore. Is that correct? It's no big deal for me to go buy a baggie of the little crimps, I just already have a ton of the correct size wire nuts because I thought I'd be able to use them for the project.

The second question - I know back in the "old times" they installed 240V circuits with 12/2 with ground - Black was Leg 1, White was Leg 2 (with red tape/flag on it), and the safety ground is the third prong.

Part 1) If I'm just running compressors/welders that just use 3 prong 240V, can I put in 3 wire outlets, or does all new work require the 12/3 with ground for a 4 wire outlet? (at which point, I would have to get an adapter, no biggie).

Part 2) If I do need to do 4 wire (12/3 w/ ground) 240V, can I run two strands of 12/2 into the box? Strand 1 would have leg 1 (black) and neutral, Strand 2 would have leg 2 (black) and neutral. Both Neutrals would be tied together at the outlet, and both safety grounds would be tied together as well. If that doesn't make sense, let me know and I'll explain better or try to draw it out and post it.

Thanks!

 

[alfredeneuman]

Q1: In more than 40 years, I've never had an inspector turn down wire nuts for a grounding connection. The connections should be made before the rough inspection.

Q2: The 2 wire cable is fine, unless a neutral is needed. Just remember to mark the white wire with tape of any color except green or gray.
(In the "old times" marking the wire wasn't even a requirement.)

 

[zmaxmotorsports]

Q1: In more than 40 years, I've never had an inspector turn down wire nuts for a grounding connection. The connections should be made before the rough inspection.

Q2: The 2 wire cable is fine, unless a neutral is needed. Just remember to mark the white wire with tape of any color except green or gray.
(In the "old times" marking the wire wasn't even a requirement.)

 

[piratius]

Q1: In more than 40 years, I've never had an inspector turn down wire nuts for a grounding connection. The connections should be made before the rough inspection.

Q2: The 2 wire cable is fine, unless a neutral is needed. Just remember to mark the white wire with tape of any color except green or gray.
(In the "old times" marking the wire wasn't even a requirement.)

Thank you so much for the very quick reply! Do I even need to twist the whole length of the safety grounds together then, before I use the wire nut?

Follow up on Question 2 - If I do want to do 4-wire 240V (for forward compatibility in case I need something later down the road) can I do the two strands of 12/2 like I asked?

-Brad

 

[jav]

just because you use the word "box" relative to the grounds I'll add my .02c.

All your grounds should go a ground bar in the (sub) panel... no wire nuts in that box.

In your wall/ceiling device boxes, approved wire nuts are still fine unless you have an inspector imposed restriction???. I use the green nuts with a hole in the end and I leave 1 ground wire long (to feed through that end hole) and I twist the others together and install the wire nut and terminate the 1 long wire at the device.

 

[jim111]

Follow up on Question 2 - If I do want to do 4-wire 240V (for forward compatibility in case I need something later down the road) can I do the two strands of 12/2 like I asked?

-Brad[/QUOTE]

Use 12/3 WG for a 4 wire setup, not two runs of 12/2

 

[wyliesdiesels]

Hold on a minute guys.

The OP mentioned using NM-b 12/3 for compressors and welders and people are saying thats ok.

Problem is, thr OP hasnt told us what the HP rating is on the compressor motor or what the input requirements are on the welder. Whoops

 

[alfredeneuman]

My reply is the same no matter what size of wire is used.

 

[piratius]

just because you use the word "box" relative to the grounds I'll add my .02c.

All your grounds should go a ground bar in the (sub) panel... no wire nuts in that box.

In your wall/ceiling device boxes, approved wire nuts are still fine unless you have an inspector imposed restriction???. I use the green nuts with a hole in the end and I leave 1 ground wire long (to feed through that end hole) and I twist the others together and install the wire nut and terminate the 1 long wire at the device.

Correct - In the electrical subpanel, all of the Grounds are to be run to the ground bar, and all of the white Neutral wires will be run to the neutral bar. No wire nuts in the electrical box!

The electrician was saying that in the blue wall boxes (2 gang) they needed metal crimps to hold the safety grounds together instead of wire nuts. I had never heard that before. I'm going to try to contact the county and see what they say tomorrow.

 

[theoldwizard1]

The electrician was saying that in the blue wall boxes (2 gang) they needed metal crimps to hold the safety grounds together instead of wire nuts. I had never heard that before. I'm going to try to contact the county and see what they say tomorrow.

If it was true, why do they make green wire nuts ?

 

[Falcon67]

St. Pattys wiring?

 

[Barnabas]

I have always used the copper crimp connectors since the early 80s. I twist the copper ground wires together to keep them away from the hot screws. I keep one ground wire long to connect to the receptacle and cut the others off after the crimp connector. I never use wire nuts on ground wires.

Link to an example.

http://www.globalelectricalsupply.com/18-8-AWG-Copper-Crimp-Sleeve-Wire-Connectors-p/sb1808.htm

 

[Dagny]

no wire nut in panel? code reference.

 

[Norcal]

no wire nut in panel? code reference.

There is no code reference.

 

[BillK]

I'm going to try to contact the county and see what they say tomorrow.

This is all that really matters. No matter what anyone else thinks or what any code says, the inspector has the final say. That goes for all of your questions.

Does Fairfax actually have their own inspectors or do they contract it out ? When you call, ask if you can talk to the guy who will actually do the inspection.

 

[wyliesdiesels]

If crimps are the only thing allowed for ground wires then it must be a local amendment.

 

[Cmreschke]

Wire nuts are a ok here in michigan. No matter what you want to pretwist the grounds for a couple inches, make the connection hold together before the wirenut is used. That's just my opinion, not code, but more professional application too.
Personally have never used a green wirenut always used reds. I have used buchanans (brand of crimp) and spliced my wires the same way there too (with a pig tail and not just a longer wire), however, if you use the crimps make sure you use the manufacturers recommended tool for install. Buchanon requires their 4 point crimper which is a 50 dollar tool.

 

[BADSIX]

just to add ,I had the inspector over and he recommended wire nuts over the crimps .maybe personal but he'll get wire nuts.
Jay D.

 

[mjbasford]

If crimps are the only thing allowed for ground wires then it must be a local amendment.

OP is in Virginia, and there are no local amendments allowed here, all done at state level.

Wirenuts are admissible here in VA, but ask your local inspector, is it really worth a fight either way?

 

[matt_i]

Its probably not worth a big fight but I'd at least ask for a code reference if they are trying to fail you over wire nutted grounds, just to point out they aren't backed by an actual standard (unless local as pointed out). I am all for pre-twisting the bare grounds.

 

[wyliesdiesels]

OP is in Virginia, and there are no local amendments allowed here, all done at state level.

Wirenuts are admissible here in VA, but ask your local inspector, is it really worth a fight either way?

Why should the OP be bulied by an inspector that doesnt know the code?

If there are no local amendments then wire nuts for grounds are code permissable.

An inspector cant just make up the rules as he goes.

 

[mjbasford]

While i completely agree with you, sometimes it it just not worth it in my opinion.

 

[TK-421]

While i completely agree with you, sometimes it it just not worth it in my opinion.

Might not be worth it only for you, but might save a guy down the road some trouble. Inspector's should know the rules they're enforcing better than anybody, and if they don't then you're doing them a disservice by not politely informing them of such.