Bonding screw question


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Old 12-02-22, 03:31 PM
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Bonding screw question

I have a 200 amp homeline breaker box im installing and I'm wondering if the bonding screw should be put in or not. This is not the main service box outside its a breaker box indoors. I was going to put the bonding screw in but it wont thread through because the way i installed the panel on a wooden support seems to not let the bonding screw thread through back side of the panel because of the board installed i hung panel on. After it wouldnt screw in it got me to thinking if i even needed it there. Info I look up says there is no need for a bonding screw past the first disconnect which im assuming means the outside main ...thanks
 
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Old 12-02-22, 06:42 PM
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Mobile homes have been using four wire connections for years.
Your new panel installation would not be considered "fathered in" which means it must be connected using four wires.
 
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Old 12-02-22, 06:54 PM
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Old setup to mobile probably allowed 3 wire feed. The feed from the main panel at meter to the new panel at cabin now needs to be 4 wire. The green is the equipment ground and needs to be connected between the panels. Make sure to have ground rods at the meter main panel and off the subpanel at the cabin. The panel at the cabin does need to have isolated neutral bar along with a bonded ground bar for the grounds and the grounding electrode conductor for ground rods placed at the cabin.
 
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Old 12-02-22, 08:15 PM
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Wires that are short can be extended via wire nutting on extensions. I will only advise you to do what is allowable by the NEC.
To not use the green EGC between panels would require the neutral be bonded which means using the bonding screw I told you to throw away to bond the bars to the panel box. Your wiring would stay as is with both neutrals and grounds on the same bar(s). This is no longer NEC compliant.
 
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Old 12-02-22, 03:58 PM
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If this is a subpanel off the main panel then the neutrals should be isolated and grounds landed on their own bar bonded to the enclosure. In other words don't use the green screw to bond the neutral bar to the enclosure.
 
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Old 12-02-22, 04:03 PM
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This is a subpanel off from the main but the grounds and neutrals are on the same bars one on left side and one on right side n and g are on both sides There are n and g on left side bar and n and g are on right side also .....these are the bars that came on the panel homeline 200 i didnt install any other bars. Thanks for your help
 
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Old 12-02-22, 04:13 PM
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Welcome to the forums.

Electrical panels come for use as a main panel.
If you are using it as a sub panel you need to connect it to the main panel with four wires and add a dedicated ground bar to the new sub panel. Neutrals and grounds don't get shared on a sub panel.

You can post a pic for further help..... How to insert pictures.
 
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Old 12-02-22, 05:41 PM
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Old 12-02-22, 06:01 PM
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Here are pictures of the older 200 amp main panel outside at the meter. The other picture is of my new sub panel installed in a cabin. I do have 4 wire running from panel to panel just not connected yet. The 3 wire connection seen in the main outside service panel goes to an old mobile home on the property that will be torn down, and that service wire removed. The new panel in the cabin is a homeline 200 amp, as you can see in picture i do have the black power wires and neutral wire connected but was told i could just omit the green ground wire from this setup....The reason i have grounds and neutrals on same bars is because when i got this box i looked up a youtube video on how to install the panel and i followed how they done the one in video. I dont know if allowed to post youtube links so ill just give the title of this video

How To Wire A Breaker Box: Square D Homeline 200 AMP

In the video he has grounds and neutrals on same bars just as i did mine....so today i went to get some 4 gauge copper wire to ground the box to a copper rod outside from the space provided in panel right by the big neutral wire, and i showed the pictures to the fella at the electrical supply store and asked him if it seemed right , he said its ok but he woulda put neutrals on one side and grounds on the other but it would be ok like i have it.....and i asked him if ok to just forget about the green ground wire and he said would be ok too. So I get home and start running the ground wire to rod and then tried to put on the bonding screw and it wont thread through because there is wood ( 2 =2 x 4s what i have panel mounted on) behind the bonding screw hole. Will I need that bonding screw in there or no? Info I looked up said didnt need one on anything past main disconnect which im assuming means after outside main panel. Thanks for any help
 
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Old 12-02-22, 06:18 PM
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Not sure what I'm looking at. Pictures of the entire panel are more helpful.
Top pic has a black neutral with white strip. Bottom pic is black wire yellow stripe.
That means the panels aren't related.

The top pic looks like a sub panel.
I don't see the bonding screw in place. I see a green ground wire. That would mean the two large bars are neutral and the green should go to its "grounds only" bar.

The bottom picture looks like the main service which means between there and your sub panel should be four wires. The ground and neutral connect to that right hand bar with the yellow strip wire.

You can leave you tube links.
 
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Old 12-02-22, 06:19 PM
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Is the metermain panel on a pole from which you ran a 4 wire feed to the cabin? I'm trying to clearly understand what's going on to give you accurate information.
 
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Old 12-02-22, 06:30 PM
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Yes meter and main panel are outside on pole the wires dont match because the old wires in main panel outside are connected to an old mobile home. Those wires and mobile home will be removed and I have new 4 wire ready to connect at the main outside panel and the top pic is of new sub panel in cabin...but since the mobile home had a 3 wire and it seems easier i was thinking of just not using the green ground wire on the new service wires. Sorry only pics I got for today.
 
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Old 12-02-22, 07:11 PM
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Thanks for all the help here I appreciate it.......The main panel outside is grounded to a rod and I am putting one in off from sub panel also at cabin .....are you meaning that i need an isolated separate neutral bar installed and put all my neutrals in subpanel on that bar? because i already have them in the bar that came on panel....it would seem near impossible to redo them as they wouldnt reach to fit ......and when you say bonded ground bar is that yet another separate bar for grounds from the runs or are you meaning for just my big green ground wire .....also i do have some bars that i was going to put om there but for some reason i cannot get them to line up with holes of box .....ive been at this a while trying to get this completed and tried and had several ideas going....i have asked about this before to people at electrical supply places and facebook groups and the more i try to figure it out what seems should be kinda simple just keep getting more confused ....sorry for dragging the questions on
 
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Old 12-02-22, 07:12 PM
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Also do i need that bonding screw in there on sub panel thanks
 
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Old 12-02-22, 07:36 PM
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The panel at the cabin is a subpanel so all the neutrals are landed on the isolated bar that came in the panel. You do not bond that bar to the panel using the bonding screw. The installed bar that came in the panel should be on plastic standoffs isolating it from the panel box. You need to add a ground bar kit to the panel for all the grounds to land on. The ground bar is directly connected to the panel box making it bonded to the panel. Throw away the green bonding screw.
Your panel looks to have bars on the left and right, those should be interconnected by a strap so both can be used for the neutrals. You need to add square-d ground bar kit(s). There are screw holes in the back of the panel for adding ground bars.
 
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Old 12-02-22, 08:01 PM
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Thanks again .....I would put the ground bars in and i might still if i can figure out how to get them to reach but the way my runs are connected i dont have much extra ground wire to reach 1 ground bar they are all already connected to bus bar right there by breakers in pic one on new sub panel......if i put in ground bars it would seem i would need to put three or 4 of them in to get them all to reach a bar......this panel will not be inspected or anything so i ask what if i connect three wires in main and three wires in sub just as pictured above and disregard the big green ground and just tape it up and push off to side on both ends (in both the main and sub boxes), then keep the grounds and neutrals like they are in pic one on new sub panel, and do NOT put in bonding screw will that work or would that be dangerous sorry for the confusing questions
 
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Old 12-02-22, 08:22 PM
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I appreciate all the help
 
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Old 12-02-22, 08:24 PM
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do you have a link to an amazon or etc product that you would suggest using to extend the ground wires? or are just meaning wire nuts? i never thought of extending the ground wires thats a big help
 
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Old 12-02-22, 08:32 PM
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Standard wirenuts, nothing special. I added additional comment to my previous post if you missed it.
 
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Old 12-05-22, 09:26 PM
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Newer panels have separate buses for neutral white wire and frame ground for bare wire that resolves issue.

Old panels with one combination neutral/frame ground bar create issues.

Adding a new separate frame ground bar:
https://www.homedepot.com/b/Electric...5yc1vZbm0jZ758

Connect all bare ground wires to new one.
Keep all white circuit wires on original circuit ground..

*Using original bar only for neutral greatly simplifies wiring.

DH did that on 1960’s Square D 30 breaker panel and it really cleaned up mess. Some #12 or #14 whites were extended with soldered crimps covered with white heat shrinkable tubing. Do not like wire nuts, especially in panels

On panels like papoa2552, installing a frame ground bar on both sides of panel would simplify wiring.
 
 

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