Subpanel boding/unbonding

[smokey_truck]

Folks

I have 100 AMP feed from my main panel through a breaker to my detached garage, I am using XXHW- AWG-2 wire. It has 2 hots (black) and one bug spirled aluminimum wire. 2 hots are connected to the breaker poles and spirled wire is connected to ground from the main panel and now on the other side I have 100 AMP subpanel.

The wierdest problem is
My ground connections:
when I connect all the big Aluminium ground to the ground lug on the ground bar and all the copper wires from the electrical circuit is connected and the ground bar is bonded by the strap to the green screw on the case

The neutral bar has all the neutrals connected to the neutral bus

I have no power and only on GFI outlet I can see the power but when I put the 3 tester it says Ground/hot reversed.

My electrician connected before all the neutrals to the bonded side and ground to the unbonded bus bar. I have all the power and the 3 tester checks out fine.

What seems to be the issue here I have no idea. Can anyone shed some light on this please.

 

[climbabout]

You are 1 wire short in your cable. Sounds like you fed this with what is called 2/3 seu cable which is normally only used on your service drop on the outside of your house to your meter and to the main breaker. In this use, the spiralled ground is used as your neutral conductor (not the same as your ground). Once you are past your main service disconnect, you should have used 2/3 SER cable which contains 3 insulated conductors (2 hots and a neutral) and also a bare ground. From your description of what you did, you are missing the neutral conductor in your subpanel.
Hope this helps,
Tim

 

[offroadsteve]

Edit: climbabout beat me to the punch, but i'll leave my post just for good measure.

A picture of your panel without the cover would be very helpful.

But, if I understand you correctly, it sounds like there are only 3 wires from the main panel in your house to the detached garage sub-panel. THIS IS INCORRECT. You should have 4 wires: 2 legs of 120v, a neutral and a ground.

It also sounds like your neutral bus is insulated from the panel box, which is correct for this type of installation, however since you have no neutral wire back to the main panel, you don't have a complete circuit, hence no power.

I don't undestand the electician's configuration, because if the grounds were run to the isolated bus bar, they would not be grounded, and your circuit tester should show an open ground. Like I said, need a picture!

Bottom line... this should be a 4 wire feed from the main panel, and you are only refering to 3 wires, which is not correct.

 

[smokey_truck]

That sounds like a big trouble now, all my wires are hurried in a conduit and concrete is poured. I have no way of getting another wire at all. Is there another way to wire this sub panel like main panel using grounding rod and connect neutral to grounding bus bar.

I am surprised the electrician did this.

Ganesh

 

[climbabout]

Can you post a picture of the main panel with the cover off and the sub panel with the cover off as well as a picture of this wire, so we can see for sure what you have?
Tim

 

[Falcon67]

I'm not advocating this, only offering an example - you should check with a local pro before changing anything.

Per older code, my old shop used three wires from a double tapped meter on the house. The shop was a detached building fed via 60A breaker. The neutral lead was attached to the neutral bus in the can and the ground bus was bonded to the can. The building had an 8' copper rod in the foundation right under the breaker can, tied in with #4. The hookup was reviewed by a licensed commercial electrician. This would be late 90s stuff.

My new shop will be as noted above - 4 wires from a double tap off the house meter, UFER ground at the shop, ground bus isolated, using SER USE-2 2-2-2-4 cable.

 

[Charles (in GA)]

That sounds like a big trouble now, all my wires are hurried in a conduit and concrete is poured. I have no way of getting another wire at all. Is there another way to wire this sub panel like main panel using grounding rod and connect neutral to grounding bus bar.

I am surprised the electrician did this.

Ganesh

Quite frankly, it sounds like your electrician is a hack.... unless we are totally mis understanding what you have.

As already noted, after the electrical disconnect (either at or near the meter, or if none there, then the disconnect in the main panel) you isolate the ground and the neutral, and keep them isolated for the rest of the system. Separate wires for ground and neutral. They should only come together in the panel or box where the first/main disconnect in the system is.

You cannot (should not) run another wire, its a code violation. In a jacketed cable, all wires are required to be in the jacket. You cannot run another loose wire to make up for what is missing in the cable. It all needs to come out, and the proper 4 wire setup installed.

Charles

 

[Steevo]

In my remote shop panel, which comes from the main panel at the house, and which was fully inspected, the wire from the main panel is three-wire, two hots and a neutral. The ground is at the shop, via rebar through the foundations, if i recall correctly. The ground and neutral are not bonded at the remote panel.

Is there any reason that the OP can't use the uninsulated 3rd wire as the neutral from the main to the sub panel, add a local ground to current code at the garage, and be in compliance?

 

[BigJohn20]

In my remote shop panel, which comes from the main panel at the house, and which was fully inspected, the wire from the main panel is three-wire, two hots and a neutral. The ground is at the shop, via rebar through the foundations, if i recall correctly. The ground and neutral are not bonded at the remote panel.

Is there any reason that the OP can't use the uninsulated 3rd wire as the neutral from the main to the sub panel, add a local ground to current code at the garage, and be in compliance?

Because having ground rods or a concrete encased electrode (what you have in your shop) is not enough to bring this installation up to current code (2008+) unless he only wants 120v at his subpanel. The ground needs to go back to the panel unless some very, very specific conditions are met.

 

[smokey_truck]

Here are pictures of and panel and sub panel

View media item 12987View media item 12986

 

[nehog]

Your electrician forgot the neutral... Sorry, I have no easy fix for you!

 

[pstnbly]

An electrician did that ? Or did he just learn to spell electrician today, WOW

 

[smokey_truck]

An electrician did that ? Or did he just learn to spell electrician today, WOW

Man I paid 1500 bucks to do amp upgrade and pull this wire to the garage through a conduit. I cannot believe he missed one wire, however I can use uninsulated as neutral and have a ground using the rod right. I believe if the sub panel is located in detached building and not connected by any metal, neutral and ground can be bonded or something along those lines I heard. I k now lot of these are to comply for code after 2008 but My question is if anything can be done based on pre 2008 code

Any inputs along those lines will help at this juncture

G

 

[Falcon67]

Looks like if your breaker run neutrals on the sub get moved to the left hand bus, you'd have power. Anybody with a bit of brain and a picture book from Lowes could have avoided that issue. I don't know enough about grounding issues on subs to say, but if the sub feed comes off the bottom of that main panel with no breaker on the feed, it might meet pre 2008 or
2006 for a service entrance feed. Which it really isn't and the whole thing is a stretch.

However - and others will fill in - tieing in the feed at the meter or at the bottom of the main panel bus' is electricly the same. Code wise - I think its going to be a sub panel, breaker on the feed or not. Interesting.

 

[climbabout]

Man I paid 1500 bucks to do amp upgrade and pull this wire to the garage through a conduit. I cannot believe he missed one wire, however I can use uninsulated as neutral and have a ground using the rod right. I believe if the sub panel is located in detached building and not connected by any metal, neutral and ground can be bonded or something along those lines I heard. I k now lot of these are to comply for code after 2008 but My question is if anything can be done based on pre 2008 code

Any inputs along those lines will help at this juncture

G

Smokey - theres no getting around it - you don't have an insulated neutral which is required downstream of your main service disconnect. If you look at the top picture of your main panel, the neutral is the middle wire above the main which connects to the 2 bars directly adjacent to where the branch breakers plug in. You say he ran this wire in conduit? If that is so, the only proper thing to do is pull it out and pull in the correct wires. As I suspected the wire he ran is SEU cable only to be used BEFORE your main disconnect. It's hard to imagine he ran that stiff wire through conduit though. Is it possible he has a junction box before the conduit somewhere and he ran single conductors through the conduit? Either way, it's wired improperly and there is only one way to make it safe. No one like to hear new like this, but safety should be your main concern.
Tim

 

[nehog]

Man I paid 1500 bucks to do amp upgrade and pull this wire to the garage through a conduit. I cannot believe he missed one wire, however I can use uninsulated as neutral

Actually, no you can't. Neutral must be insulated.

and have a ground using the rod right. I believe if the sub panel is located in detached building and not connected by any metal, neutral and ground can be bonded or something along those lines I heard. I k now lot of these are to comply for code after 2008 but My question is if anything can be done based on pre 2008 code

Any inputs along those lines will help at this juncture

G

Since you paid someone to do the job, he should have been a licensed electrician. It's his job to fix it, his nickel (since he screwed it up) and if he won't fix it for you free, file a complaint with the regulating board or whoever licenses electricians in your state/locality.

Again, the neutral is missing, there is no easy fix. A new cable needs to be pulled (not an additional neutral wire, that won't work.)

 

[mrb]

and WHATEVER you do dont keep the existing feeder, isolate the neutral and ground, add a ground rod and think youre ok. People have been killed from this sort of thing.

 

[mrb]

Did your handyman install SE cable underground in conduit? I though SE couldnt go underground as its not ok for wet location....

 

[BigJohn20]

Did your handyman install SE cable underground in conduit? I though SE couldnt go underground as its not ok for wet location....

It can't. SE is not listed for underground but it is listed for wet location and sunlight exposure. USE may be installed underground.

 

[smokey_truck]

What if I use unisulated as neutral and take one extra wire for ground and send in a metal conduit up to the detached garage. Ground doesnot have to be burried 24" deep right. Will that work or would it be even code violation.

I am just afraid to pull the wire our and then have troubel to fish more wires through the conduit. That would be a disaster as I cannot break the concrete to do all this.

 

[climbabout]

What if I use unisulated as neutral and take one extra wire for ground and send in a metal conduit up to the detached garage. Ground doesnot have to be burried 24" deep right. Will that work or would it be even code violation.

I am just afraid to pull the wire our and then have troubel to fish more wires through the conduit. That would be a disaster as I cannot break the concrete to do all this.

You CANNOT use an unisulated conductor for a neutral after your main service disconnect. Period. There is only one way to fix this and that is the right way. Electricity is a dangerous unforgiving beast that needs to be done correctly to be safe. Just because you can jerry rig something to work, does not make it safe. If the installer put conduit in, then disconnect the wire at both ends, fasten a snake or pull rope to one end and pull it out from the other end. Use the snake or pull rope to pull the proper wires in.

Tim

 

[Charles (in GA)]

If the conduit was put in using long sweep ells and is of decent size (hopefully more than 1-1/2 inch) it should not be a problem to pull the existing wire and pull in new wire. What you need is a four wire quadplex such as aluminum mobile home feeder, or copper THWN wire of the appropriate size. These will pull much easier than a jacketed cable, which you do not need.

As already noted, the neutral is a hot wire, and must be insulated, and code does not allow a separate wire to be run either with a jacketed cable or in other conduit to make up a circuit. It either needs to all be in the same jacket, or all needs to be loose wires in the same conduit.

Charles

 

[Aceman]

I agree with the other posters. This installation is so hosed up, there is no saving it. You can only refeed with all new wire at this point.

Did your electrician pull a permit?

 

[samert111]

If the conduit was put in using long sweep ells and is of decent size (hopefully more than 1-1/2 inch) it should not be a problem to pull the existing wire and pull in new wire.

I'm not sure he can fit another #2 wire in that conduit for the neutral coming off the main panel shown in the first photo. Isn't there a minimum clearance required in conduit based on wire size? If that's the case he could drop down in amperage to his garage with smaller feed wire and breaker in the main.

Also, it looks like the neutral feed to the main panel is uninsulated or maybe the insulation is just stripped higher up and not showing in the photo. Is this OK? The neutral feed in my house main panel is insulated just like the hots.

 

[Motofixxer]

I'm no expert...but it needs to be pulled and replaced properly. Pull a pull rope when you pull the old stuff out. Worst case use a string attached to a plastic bag and use a vacuum. Then pull a rope etc, then pull your wire, use some wire lube for good measure. If the conduit was sized near properly it shouldn't be any trouble at all. There is no way this has been inspected. If you paid an actual electrician, then it's his responsibility to wire it properly at his cost.

 

[Charles (in GA)]

I'm not sure he can fit another #2 wire in that conduit for the neutral coming off the main panel shown in the first photo. Isn't there a minimum clearance required in conduit based on wire size? If that's the case he could drop down in amperage to his garage with smaller feed wire and breaker in the main.

Also, it looks like the neutral feed to the main panel is uninsulated or maybe the insulation is just stripped higher up and not showing in the photo. Is this OK? The neutral feed in my house main panel is insulated just like the hots.

I still haven't figured out the pics yet. If the lower one is the garage, what is the large white wire on the RH side bar?

On the house panel, its quite possible that he has two hots and the spiraled metal inside the jacket supplying it, as it would have a combined ground/neutral from the meter to that panel (assuming there are no other disconnects between the meter and the panel.)

Charles

 

[Scamilleri1228]

Samert111 yes it's ok to have an insulated neutral in a main panel but it isint required. The code requires you to run 4 wires to the sub panel. All four wire must be in the same conduit or raceway. I would see if you can disconnect the wire at both ends and give it a tug. If it will move it will come out. At that point you could run single stranded wire like thhn. That will probably pull easier with a little cable lube it shouldn't be a problem. At this point we should see. If the conduit is sized right too. Btw looking at the pick did I see more the one white wire (neutral) under the same screw? That's a no no as well. One neutral per screw however the grounds (green or bare copper) can share a screw. I'm sure you know that the can be on the same bars in the main panel, however the sub the neutrals must be separate from the grounds.

 

[samert111]

I still haven't figured out the pics yet. If the lower one is the garage, what is the large white wire on the RH side bar?

It appears to be the same size as the 2 hots on the lower left side going to the Dbl breaker and the ground for it appears to be about 1/3 up from the bottom on the ground bar. So he has a 3 wire + ground going out to something. Maybe a 220V 50 amp RV outlet as they need the neutral since nothing in an RV uses 220V and needs the neutral for all circuits.

 

[kngelv]

Wow what a mess. What size conduit is that cable in? You need to fix this correctly. Don't try some half-a** fix. If the conduit size is ok pull that cable out and run 4 individual conductors as other posters have mentioned. Putting service cables in conduit is almost never a good idea. Obviously the so called electrician who did this install does not have a clue. The wiring in the panel is sloppy too. I would also recommend driving a ground rod outside your garage and tying that to the panel in addition to the ground coming from the house. BTW I'm a Journeyman Electrician.

James

 

[climbabout]

Good reply James - here in CT not only is the ground rod a good idea - it is a code requirement for a detached structure.

Here you have confirmation from another licensed electrician of the same advice from most of the rest of us. Make this safe!

Tim

 

[kngelv]

Good reply James - here in CT not only is the ground rod a good idea - it is a code requirement for a detached structure.

Here you have confirmation from another licensed electrician of the same advice from most of the rest of us. Make this safe!

Tim

Thanks. Some cities require it while others don't, but I always recommend it.

James

 

[smokey_truck]

Thanks to everyone for your inputs, today I was able to pull 4 way wire and took that 3 wire off. All wired according to code and everything is working great. That electrician who pulled was a mess.
Thank God I could tail to new wire to old wire and came through conduit perfectly.

Ganesh

 

[kngelv]

That's great to hear. Did you go ahead and drive a new ground rod next to the garage?

James

 

[Norcal]

That's great to hear. Did you go ahead and drive a new ground rod next to the garage?

James

Please be aware that two rods are required unless you can prove 25 Ohms of resistance or less, & the testing equipment is very exspensive.

2008 NEC 250.56


250.56 Resistance of Rod, Pipe, and Plate Electrodes. A
single electrode consisting of a rod, pipe, or plate that does
not have a resistance to ground of 25 ohms or less shall be
augmented by one additional electrode of any of the types
specified by 250.52(A)(4) through (A)(8). Where multiple
rod, pipe, or plate electrodes are installed to meet the requirements
of this section, they shall not be less than 1.8 m
(6 ft) apart.
FPN: The paralleling efficiency of rods longer than 2.5 m
(8 ft) is improved by spacing greater than 1.8 m (6 ft).

 

[BFBOB]

As others have said, no easy fix. Doing a difficult pull once I rigged a pulley on the eaves to get a straight pull through the conduit, tied the pull wire to the trailer hitch of my van and pulled away! (slowly and gently, of course). There's always a way to get enough pull to get the old stuff out--winch, come-along. Pulling the new in, use wire **** (oops, I meant pulling compound), individual stranded conductors , not cable, and the pull will be much easier, even though there's more wire. Better yet, use copper; it's much smaller and easier to pull. (of course, there is one disadvantage to copper: $$$$)

All this is assuming your highly trained professional electrician won't correct his mistake free.

 

[kngelv]

Please be aware that two rods are required unless you can prove 25 Ohms of resistance or less, & the testing equipment is very exspensive.

2008 NEC 250.56


250.56 Resistance of Rod, Pipe, and Plate Electrodes. A
single electrode consisting of a rod, pipe, or plate that does
not have a resistance to ground of 25 ohms or less shall be
augmented by one additional electrode of any of the types
specified by 250.52(A)(4) through (A)(8). Where multiple
rod, pipe, or plate electrodes are installed to meet the requirements
of this section, they shall not be less than 1.8 m
(6 ft) apart.
FPN: The paralleling efficiency of rods longer than 2.5 m
(8 ft) is improved by spacing greater than 1.8 m (6 ft).

I think you need to take a closer look at Article 250. This is an outbuilding and requires only one ground rod. The one at the garage is supplemented by the ground conductor coming from the house panel. He also does not need to meet the 25 ohm requirement at the garage. This assumes of course that the grounding system at the house is correct and he has sized his ground conductor from the main panel correctly.

James

 

[Daniel Dudley]

I am not an electrician, but I have three wires running from the house to the barn. The ground and neutral are tied together in the sub panel, and the sub panel is grounded to ground with two rods.

People wired outbuildings like this for almost 100 years. The electrical inspector approved this 10 years ago, and said it was well done, so go figure.

 

[Norcal]

I think you need to take a closer look at Article 250. This is an outbuilding and requires only one ground rod. The one at the garage is supplemented by the ground conductor coming from the house panel. He also does not need to meet the 25 ohm requirement at the garage. This assumes of course that the grounding system at the house is correct and he has sized his ground conductor from the main panel correctly.

James

Perhaps you should quote where only one is required, the NEC says nothing about a exception for outbuildings.....

 

[kngelv]

Perhaps you should quote where only one is required, the NEC says nothing about a exception for outbuildings.....

250.32 Buildings or Structures Supplied by a Feeder(s) or Branch Circuit(s).
(A) Grounding Electrode. Building(s) or structure(s) sup- plied by feeder(s) or branch circuit(s) shall have a ground- ing electrode or grounding electrode system installed in accordance with Part III of Article 250. The grounding electrode conductor(s) shall be connected in accordance with 250.32(B) or (C). Where there is no existing ground- ing electrode, the grounding electrode(s) required in 250.50 shall be installed.
Exception: A grounding electrode shall not be required where only a single branch circuit, including a multiwire branch circuit, supplies the building or structure and the branch circuit includes an equipment grounding conductor for grounding the normally non–current-carrying metal parts of equipment.

You know the N.E.C. never even mentions the word "sub-panel". Article 250 is the most misunderstood part of the N.E.C. BTW 250.56 is being dropped from the 2011 code. Some of the sub-sections are contradictory. Based on the entirety of article 250 you could argue that as long as you pull a ground conductor from the main panel you do not need ANY ground rod at the garage. Some inspectors want a ground rod some do not. Hell some of them are still using the 1996 code. On a side note. I hope all of the guys doing their own work are NOT bonding the neutral at the sub.

James

 

[mtne]

I am not an electrician, but I have three wires running from the house to the barn. The ground and neutral are tied together in the sub panel, and the sub panel is grounded to ground with two rods.

People wired outbuildings like this for almost 100 years. The electrical inspector approved this 10 years ago, and said it was well done, so go figure.

Inspected doesn't mean it's right. The only point at which the neutral and ground are to be bonded are at the first point of service. Period. End of story. I'd go ahead and take the bond screw/strap out if it's as easy as that.