Go Back  DoItYourself.com Community Forums > Electrical, AC & DC. Electronic Equipment and Computers > Electrical - AC & DC
Reload this Page >

Need advice on cleaning up wires in service panel and AFCIs

Need advice on cleaning up wires in service panel and AFCIs

Reply

  #1  
Old 05-21-12, 09:08 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Need advice on cleaning up wires in service panel and AFCIs

Hello all,

In my service panel I noticed that neutrals are under the same screws as grounds in many cases. I read somewhere that you cannot have neutrals and grounds under the same screw. I've been working on separating the grounds from the neutrals but I have some questions.

1) Only 1 neutral per screw right?
2) Only grounds of similar gauge under one screw right?
3) What is the maximum amount of grounds to put under one screw? I've been doing 3.
4) There are some larger screws that look like they are mean't for thick wires like 6 gauge wires. Is it ok to stick multiple grounds under these screws? I was just wondering since the 14 gauge wires are small couldn't they come loose?
5) Are you supposed to twist the grounds together before putting on one screw? None of them are twisted.
5) I've been wiring some AFCIs. They come with pigtails that connect to the neutral bus bar. Should I trim them to the length I need or leave the full length of wire? The reason I have not trimmed them yet is because I am still working on cleaning up the panel and don't want to end up with the pigtail being too short if I have to move something around. AFCI = $$$
6) After installing AFCIs I have had to pigtail two neutrals so far so they could reach the AFCI. I've twisted the pigtail using pliers than I put a nut around it. I then bundled the pigtail with the rest of the neutrals/grounds. Does that sound ok?
7) On my panel all the neutrals/grounds are mixed up. I don't think it would be possible to have neutrals on one side and grounds on the other side because of wire length. You'd probably need a ton of pigtails to separate them like that. Does this sound ok the way it is?
8) Since there are 38 spots used out of 40 in my panel, the wiring is hard to trace since there is so much. I am pretty sure I've wired the AFCI's correctly but is there an easy way for me to double check that I have connected the neutral to the AFCI corresponding to the hot that I've wired to the AFCI? What I mean to say is, can I double check if the neutral and hot connected to the AFCI are from the same NM wire?

Thanks all.
 
Sponsored Links
  #2  
Old 05-22-12, 08:44 AM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Since there are 38 spots used out of 40 in my panel, the wiring is hard to trace since there is so much. I am pretty sure I've wired the AFCI's correctly but is there an easy way for me to double check that I have connected the neutral to the AFCI corresponding to the hot that I've wired to the AFCI? What I mean to say is, can I double check if the neutral and hot connected to the AFCI are from the same NM wire?
You can pick up a book of wire marker labels at your local supply house if you don't see them at the big box store. The book you're looking for will have 10 or more sheets with 3 rows of 15 labels on each sheet. The labels on each sheet will be numbered 1 through 45. Each vertical label will be a strip with 6 numbers on it and a perforation allowing it to be separated into two strips of 3 numbers. There will be a single number tag at the bottom of each 6-number strip. Those are handy for tagging a circuit on the face of the breaker, or on the deadfront next to it.

With at least 10 pages of labels which can yield two strips per circuit number, you will have 20 or more wire labels available for each circuit - enough for each hot, neutral, and neutral pigtail several times over. Just wrap a label strip around each wire an inch or two back from the end of the insulation. Orient it so that you can read the number clearly when the wire is terminated.

Note 1: The labels adhere permanently, but you can usually peel them off and move them to a different wire if you're moving circuits around - at least once or twice.

Note 2: You may already know this, or it may be clear from your panel markings, but the circuits are numbered 1 through 39 down the left side of the panel and 2 through 40 down the right side. That's one number per full-height (1") breaker space. If you have any tandem, or half-height (1/2") breakers, they will be in pairs and each individual breaker in a pair is designated with an "A" or a "B," in order. For example, if you have a pair of tandem breakers in the slot for circuit 5 (third down on the left), the two circuits connected there would be "5A," upper, and "5B," lower. If you have some of those, look for a book of labels that also has some letters in it; often they are on a couple of sheets in the back.
 
  #3  
Old 05-22-12, 08:55 AM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Thanks but my issue is more of I'd like to do something with a voltmeter or some trick or tool to verify the hot and neutral I am using is coming out of the same NM wire when connected to an AFCI.
 
  #4  
Old 05-22-12, 09:01 AM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Also does anyone know the answers to my other questions?
 
  #5  
Old 05-22-12, 10:15 AM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Thanks but my issue is more of I'd like to do something with a voltmeter or some trick or tool to verify the hot and neutral I am using is coming out of the same NM wire when connected to an AFCI.
I don't know how a meter or other tool might be used to do that. If the wires are so interwoven in your panel that you can't follow a pair by sight, it may be time to turn a breaker or two off, de-terminate the wires, and straighten their paths so that you can be sure which are paired.
 
  #6  
Old 05-22-12, 03:57 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
I figured I'd have to do it that way.
 
  #7  
Old 05-22-12, 05:52 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,391
1) Only 1 neutral per screw right?
Correct. I believe the NEC addresses that.
2) Only grounds of similar gauge under one screw right?
Similar gauge and same material. Copper and aluminum grounds should be kept separate.
3) What is the maximum amount of grounds to put under one screw? I've been doing 3.
I believe the panel label should tell you exactly how many ground wires can go under a particular screw, check it and see. I think Cutler Hammer may allow up to 3. Rule of thumb is 2 ground wires per screw.
4) There are some larger screws that look like they are mean't for thick wires like 6 gauge wires. Is it ok to stick multiple grounds under these screws? I was just wondering since the 14 gauge wires are small couldn't they come loose?
Check panel label or catalog specs on panel.
5) Are you supposed to twist the grounds together before putting on one screw? None of them are twisted.
No
6) After installing AFCIs I have had to pigtail two neutrals so far so they could reach the AFCI. I've twisted the pigtail using pliers than I put a nut around it. I then bundled the pigtail with the rest of the neutrals/grounds. Does that sound ok?
I wouldn't twist, just install proper size wire nut.
7) On my panel all the neutrals/grounds are mixed up. I don't think it would be possible to have neutrals on one side and grounds on the other side because of wire length. You'd probably need a ton of pigtails to separate them like that. Does this sound ok the way it is?
Sounds OK to me.
 
  #8  
Old 05-22-12, 06:10 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Thanks for your help! I'm not sure I'll be able to do 2 grounds per screw due to the amount of wires in the box. I will have to work on it very carefully. Hopefully the panel supports 3 per screw.
 
  #9  
Old 05-22-12, 06:15 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,391
Thanks for your help! I'm not sure I'll be able to do 2 grounds per screw due to the amount of wires in the box. I will have to work on it very carefully. Hopefully the panel supports 3 per screw
OR......you could install an auxilliary ground bar.
 
  #10  
Old 05-22-12, 06:27 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
I don't think any of the ground wires would reach it. I don't think I need 10 more pigtails in the box. =/
 
  #11  
Old 05-22-12, 06:39 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Here are some pics of the panel I took a while ago. These picture do not include the most recent changes. You'll see that the panel is almost maxed out. You'll also see a lot of neutrals and grounds on the same screws. I have isolated many of the neutrals on their own screws but have not completely taken care of all neutrals yet. Unfortunately the pictures do not show the bottom of the panel. The bottom is the only place I can think of where to add grounds somewhere but I don't think the ground wires would reach it without pigtailing.

The panel is a Murray LC240PC (seems like it was replaced with model LC4040B1200) 200A panel with 40 spaces.

imgur: the simple image sharer
imgur: the simple image sharer
imgur: the simple image sharer

Could I extend the current ground/neutral bars? Any thoughts?
 
  #12  
Old 05-22-12, 08:44 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: Twin Cities, MN
Posts: 12,284
You could install some ground bars and move just the grounds to them. They attach directly to the steel case of the panel.
 
  #13  
Old 05-22-12, 09:25 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Looking at your pics I'm seeing a lot of unused terminals on the ground bar on the left. Is there a reason not to move some of the wires there?
 
  #14  
Old 05-23-12, 05:27 AM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Nashkat1 - These pictures were before the changes I've made recently. I moved a lot to the left ground bar already. Both ground bars are full. The right ground bar was super packed in these pictures before I moved things around.

PMTolyn - Where would be the best place to install the ground bars? Right under the current ground bars? Do I need Murray ground bars to be code compliant?
 
  #15  
Old 05-23-12, 07:19 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,391
If you check the label on the door, there are probably holes from the factory for Murray auxilliary ground bars. My guess is they also provide you with the Murray catalog number for them as well.
 
  #16  
Old 05-25-12, 01:57 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
The label on the panel says I can put 2 wires per small hole and 3 wires per large hole. I moved all of the neutrals to their own holes. The bar on the left side of the panel is maxed out. The bar on the right side of the panel is maxed out. I have about 20 ground wires that have no where to go right now. I am going to purchase a couple of those auxilliary ground bars. I have a few questions:

1)The ground bar holes are near the bottom of the panel. Most of the grounds will not reach that far. Do I have to use an individual wirenut to extend each wire or can I do a few grounds of the same gauge per wire nut? ie - 3 short wires would be spliced to 3 new ground wires which I would use to connect to the new ground bar at the bottom of the panel.

2) I found 4 ground wires spliced into a wire nut with 1 of those ground wires connected to a ground bar hole. Isn't this wrong? Doesn't this reduce the ground capacity of the 3 circuits?

3)Would there be any problem with me making my own holes in the panel near the top so the ground wires can reach the ground bar without splicing any connections?

Thanks all.
 
  #17  
Old 05-25-12, 02:24 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
3)Would there be any problem with me making my own holes in the panel near the top so the ground wires can reach the ground bar without splicing any connections?
That should be fine. I've done that a bunch of times on closely-inspected jobs, w/no problem.

FYI, sand or scrape the paint off of the area where the new ground bar will sit against the can, to ensure a good bond.
 
  #18  
Old 05-25-12, 02:26 PM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 14,590
Why do you have that many wires in the box? It sounds like too many circuits originate in your panel. Normally one ground bus is enough.
 
  #19  
Old 05-25-12, 03:04 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
I don't think there are too many wires in the panel. I'm not even using tandem breakers. I have 38 breakers installed out of 40. There is about 39 cables going into the panel (one is not hooked up yet) and a few ground wires. If I put each neutral in one hole (like I've been told) it takes up more than half of the ground holes. Don't ask me why.
 
  #20  
Old 05-25-12, 03:11 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
I purchased some ground bars from my Murray distributor. They only carried "electriCenter" ground bars. Is that ok? It looks exactly like a Murray ground bar. Is there any rules about only using Murray ground bars in a Murray panel?
 
  #21  
Old 05-25-12, 03:21 PM
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,399
Often the panel manufacturer will assume a certain percentage of the circuits installed will be 240 volt only and therefore not supply a terminal for a neutral conductor.
 
  #22  
Old 05-25-12, 03:57 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Is there any rules about only using Murray ground bars in a Murray panel?
There shouldn't be. For years we've kept a supply of GE ground bars on hand and used them in any panel that needed one, regardless of who made it. The GE bars were readily available, reasonably priced and easy to work with.
 
  #23  
Old 05-25-12, 06:42 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Ok the battle is going well so far. Here is what I did:

1) Since there was not much room at the top of the panel I decided to install two ground bars in the factory supplied locations. I screwed in the ground bars nice and tight and tested that they were grounded by using a voltage tester.

2) I spliced equivalent gauge copper ground wire to the existing ground wires and twisted them nice and tight using pliers. I then connected them to the ground bars I added. I am completely finished the left side of the panel. I have about 8 more ground wires to do on the right side.

Thanks for all of your help everyone!!! The panel is definitely following code better now and is a lot cleaner!
 
  #24  
Old 05-25-12, 07:18 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 33,053
I spliced equivalent gauge copper ground wire to the existing ground wires and twisted them nice and tight using pliers.
Did you use wire nuts or equivalent connectors?
 
  #25  
Old 05-25-12, 07:57 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
No I did not use wire nuts since they are grounds. Are they required to be nutted in a service panel?
 
  #26  
Old 05-25-12, 08:02 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
I just did some Googling and it appears that grounds need wire nuts too. It will be simple for me to add the wire nuts, thanks for looking out!
 
  #27  
Old 05-25-12, 08:05 PM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 14,590
Good catch Ray.

.........................................
 
  #28  
Old 05-25-12, 08:36 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Did you use wire nuts or equivalent connectors?
So a crimp connector would be acceptable?

I'm thinking that in-line untwisted crimp-connected splices would be cleaner and less space-consuming that twisted splices with wire nuts. Tho OP could even make a U-bend in the end of each wire and use the crimp connector to hold all four pieces together, for additional protection against separation, and still come out with a cleaner job.
 
  #29  
Old 05-25-12, 08:57 PM
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,399
Yes. I have often used Buchanan steel crimp caps to consolidate and extend equipment ground conductors. Of course, I also use the proper tool for the crimp caps, something most DIYers would rather not purchase due to the high cost.
 
  #30  
Old 05-25-12, 09:23 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
the proper tool for the crimp caps
There's a special tool for that? What would that be? I've used my linesmans, my BX trimmers and my dykes, sometimes in combination.
 
  #31  
Old 05-25-12, 09:50 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
I'll buy the special tool. I'd rather not have 20 wire nuts in the panel. What is it?

Even using the crimps on my twisted splices will save a lot of space
 
  #32  
Old 05-25-12, 11:09 PM
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,399
Do a Google for Buchanan C24 pressure tool (or Ideal Buchanan C24 pressure tool). List price is around $75 but I saw a used one on Ebay with a $15 bid. Amazon has some at $47.49.

The C24 puts a four-way crimp in the sleeve. If you use the copper sleeves you still need to pre-twist all the wires but this twisting is not required if you use the steel sleeves.
 
  #33  
Old 05-26-12, 08:39 AM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Does that tool work with any kind of crimps? This is what Home Depot carries:

14 - 8 AWG Copper Crimp Connectors (50-Pack)-10-311C at The Home Depot
 
  #34  
Old 05-26-12, 01:54 PM
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,399
Yes, it will work with those crimps. Be sure to tightly twist the wires before crimping when using copper crimps.
 
  #35  
Old 05-26-12, 02:25 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 33,053
Furd, those looked more like caps than butt connectors. If I'm right wouldn't butt connectors be better?
 
  #36  
Old 05-26-12, 03:00 PM
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,399
They are barrel crimps. You can run them in line if necessary.
 
  #37  
Old 05-26-12, 05:15 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 33,053
Thanks.

...........................................................................
 
  #38  
Old 05-26-12, 06:53 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Thanks Furd. I will order the Ideal C24 tool from Amazon and get the copper crimps from Home Depot.

Yes I pretwisted the grounds tightly. I just need to get this tool to finish the job and put the cover back.
 
  #39  
Old 05-26-12, 09:29 PM
Member
Join Date: Jul 2011
Location: us
Posts: 6
You could just turn off the circuit and use an ohm meter to verify. If you are separating the grounds and neutrals the neutral bar should be isolated from ground and the ground bar should be bonded to the box. There is typically a green screw that is ran through the neutral bar and into the panel to bond it, this should be removed. I would not use the large hole for the 12 and 14 wires, multiple wires in the small holes are fine.

The wires not being long enough is always an issue on a renovation project like this. All you can do is splice them to reach. just use wire nuts for the splices.

Im sure i didnt answer all your questions but maybe this will help you out some.

Mod note: Poster is only partly correct. If the box contains the first breaker or fuse (OCPD) then the neutral bar is NOT isolated from ground. It is bonded to the box. Only in subpanels is the neutral isolated.

Mod note: The OP earlier determined the maximum allowable number of ground wires in each of the different-size holes in the ground bar (Post #16).
 

Last edited by Nashkat1; 05-26-12 at 10:44 PM.
  #40  
Old 05-27-12, 09:11 AM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 305
Thanks for the ohm meter tip. After I cleaned up the wires I was able to verify that all the AFCIs were correctly wired. Just waiting on the crimp tool to finish the job, thank you!
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes