Electricians - bonding ground wires in a sub panel

[boomerang]

Selling my home. Buyer had an inspection done. Inspector is saying that grounding was done incorrectly in a sub panel in the attached garage that is fed from the main panel. Buyer wants it corrected by a licensed electrician. But I am not certain that the inspector is correct in his assessment.

The sub panel is being fed by three wires. My quick research shows that a bonded bus for the grounds is required in a sub panel fed by four wires. In a three wire sub panel, the neutrals and the grounds can be attached to the same floating bus which is how it has been done. I'm not an electrician but it seems to me that in a panel fed by three wires, if the grounds are on a bonded bus, they will have no path to ground and that they must be attached to the same floating bus as the neutrals. Yes, how I am relating this is, I'm sure not how an electrician would say it but I am hoping that I have explained it clearly.

Regardless of whether this was done correctly or not, I must have an electrician out. I guess I'm wondering whether a pissing match will result if the work has in fact been done correctly. What electrician is going to take the time to put something in writing that refutes what a licensed inspector working for a national inspection company has cited? Should I have this looked at through a GC? I have a friend who is one. I'm thinking he might be in a better position to argue this case should it need to be. Things are picking up here and the trades are starting to get busier than they have been for a long time. The electrician that did the work many years ago is making noises like he's way too busy to come out to even look at this but I have not given up on him yet.

I also need some GFCI work done and there is some moisture damage in the roof sheathing in the garage from a leak around a can vent that needs to be corrected.

Out of the laundry list of sometimes picky shit the inspector came up with I feel that the buyer is making reasonable requests and ignoring the crap. This is a good thing.

 

[momeNt]

Selling my home. Buyer had an inspection done. Inspector is saying that grounding was done incorrectly in a sub panel in the attached garage that is fed from the main panel. Buyer wants it corrected by a licensed electrician. But I am not certain that the inspector is correct in his assessment.

The sub panel is being fed by three wires. My quick research shows that a bonded bus for the grounds is required in a sub panel fed by four wires. In a three wire sub panel, the neutrals and the grounds can be attached to the same floating bus which is how it has been done. I'm not an electrician but it seems to me that in a panel fed by three wires, if the grounds are on a bonded bus, they will have no path to ground and that they must be attached to the same floating bus as the neutrals. Yes, how I am relating this is, I'm sure not how an electrician would say it but I am hoping that I have explained it clearly.

Regardless of whether this was done correctly or not, I must have an electrician out. I guess I'm wondering whether a pissing match will result if the work has in fact been done correctly. What electrician is going to take the time to put something in writing that refutes what a licensed inspector working for a national inspection company has cited? Should I have this looked at through a GC? I have a friend who is one. I'm thinking he might be in a better position to argue this case should it need to be. Things are picking up here and the trades are starting to get busier than they have been for a long time. The electrician that did the work many years ago is making noises like he's way too busy to come out to even look at this but I have not given up on him yet.

I also need some GFCI work done and there is some moisture damage in the roof sheathing in the garage from a leak around a can vent that needs to be corrected.

Out of the laundry list of sometimes picky shit the inspector came up with I feel that the buyer is making reasonable requests and ignoring the crap. This is a good thing.

Then if there is a fault in the neutral, everything will continue to work, and all the current will be going through the ground, touch the panel and zap!

From the mike holt forums in 2002

Frequently Asked Question: Why do the grounds and neutrals need to be separated in a subpanel? What happens if they aren't?

Answer: Though the neutral doesn't have significant voltage, it does carry current. Remember, it's current that kills, not voltage. In a 2-wire circuit, the neutral carries just as much current as the hot conductor. If the neutral and ground are connected in a subpanel, that current will travel on other paths, such as bare ground wires, equipment enclosures, and metal piping systems, on its way back to the service panel. One problem created by this condition is possible shock hazards, the severity of which depends on the locations of the equipment and the person touching the enclosure or piping system. Another problem is magnetic fields that do not cancel themselves out. Since the return current has multiple paths, the current remaining in the neutral will not counterbalance the current in the hot wire. The resulting imbalance creates a magnetic field that can interfere with sensitive electronic equipment. In a metal conduit system, the imbalance will induce current into the conduit, which could cause the conduit to overheat.

Q: Given that this is a fairly common condition, why don't we hear about problems, and why do some electricians not understand the problem?

A: For the feeder from one panel to another, the neutral only carries the imbalanced load between the two hot legs. Most of the time, the amount of current on the neutral is very low. However, in a situation where a single 120-volt appliance is in use, and there are few other loads in operation, the current on the equipment grounding conductors and other paths could be quite high, resulting in the problems noted above. Other conditions could cause the load imbalance to be quite high, if for example, all the lights in use at a given time just happened to be originating from the same phase conductor.

The National Electrical Code (NEC) has prohibited re-grounding the neutral after the service since the 1923 edition. Exceptions have been made for dryers and ranges that use the neutral as a grounding means, and for separate buildings. However, those loopholes have been effectively closed in the 1996 and 1999 editions of the NEC. The references in the 1999 edition of the NEC are found in 250-24(a)(5), 250-142(b), and 384-20.

 

[stormkroe]

I'll have to check nec, but cec states that neutral and ground must diverge at the first point of disconnect (usually the main breaker). Technically it should have 4 conductors in the sub feeder cable, and even have the neutral/ground interconnect screw removed inside the sub panel (usually brass or green, in the neutral bar).
As a fix, you could drop a secondary grounding electrode outside the garage and run it into the sub panel. I prefer plates to rods for ease of use.
I'm sure one of the guys working in the US can give you the nec version before I can find it, as I don't keep one in my work truck.

 

[boomerang]

I'll have to check nec, but cec states that neutral and ground must diverge at the first point of disconnect (usually the main breaker). Technically it should have 4 conductors in the sub feeder cable, and even have the neutral/ground interconnect screw removed inside the sub panel (usually brass or green, in the neutral bar). As a fix, you could drop a secondary grounding electrode outside the garage and run it into the sub panel. I prefer plates to rods for ease of use.

But that grounding electrode would have to be bonded to the existing grounding electrode, correct?

The picture I was supplied in the inspection report was a closeup of the neutral and ground wires in what appeared to be the same floating bus. I have now downloaded the full report and find that there is another picture showing the inside of the entire panel. That buss is not floating, it is bonded. Look for the green screw on the right.

So, is this Kosher? I'm just trying to learn something at this point.

As an aside, I went and bought a GFCI tester and all three of the GFCI's that the inspector said were bad, are in fact good. The TEST and RESET buttons worked fine but the actual tester also shows them to be functioning properly. I now have zero confidence in this inspector the buyer hired. I guess I'm going to find out what kind of battle this is going to turn out to be.

The kitchen is not GFCI protected. I have no problem with correcting that.

 

[momeNt]

I'm not an electrician, but isn't the fact that it is bonded the problem? I believe bonded subpanel is a violation period, the the neutral deteriorates, the ground can carry the current.

http://www.mikeholt.com/forum/Forum1/HTML/003455.html - this discusses basically your exact issue.

 

[stormkroe]

It looks like the nec has put an end to 'neutral-as-bond' exceptions, you as of today, your setup is not up to code.
To answer your question, yes you do have to interconnect the different grounding electrodes, but it's usually easier to do that than re-pull a sub feeder with the proper number of conductors. It can take a totally different and more direct path. Depending where everything is located, it could just be a short jumper outside between the old rod and the new. For that matter, you could probably just connect directly to the original electrode.
The only loophole you might have is, 'what right do they have to make you pass current codes, and who decides where it ends'? Are they going to make you change most of your breakers to arc-faults next?

 

[boomerang]

For that matter, you could probably just connect directly to the original electrode.
The only loophole you might have is, 'what right do they have to make you pass current codes, and who decides where it ends'? Are they going to make you change most of your breakers to arc-faults next?

Yeah, that's the bigger question and I had a lengthy conversation with a friend of mine that happens to be an electrician about just that subject. All homes met code at the time they were built. What is the extent to which a home needs to be brought up to current standards? My guess is that it is going to vary across the nation. Here at least, there is no municipal inspection process on a home sale. An inspection will occur if the buyer wants one and it is done by whomever the buyer hires. The buyer pays for it too.

Both of my brothers-in-law sold homes within the last few years and the cities they lived in put them through the wringer. A different inspector every visit to inspect that the previous correction was done to their requirements and each new inspector found... something new. The process was nearly never ending. My one BIL's wife was retired from a municipality where she was in charge of payroll. She eventually called people she knew there who called people they knew at the city where their home resided telling them to knock it off. It worked, no more inspections. That's an interesting situation in itself.

I wish I knew the answer to your question because I'd like to know myself but maybe I'll have one before all this is over.

 

[boomerang]

I'm not an electrician, but isn't the fact that it is bonded the problem? I believe bonded subpanel is a violation period, the the neutral deteriorates, the ground can carry the current.

http://www.mikeholt.com/forum/Forum1/HTML/003455.html - this discusses basically your exact issue.

I'm no electrician either and am frankly just confused at this point. I used to be a whiz at car electrics but am very much out of practice. Household stuff I have a bit of an understanding about but anything where codes become involved, I have to research and then don't necessarily trust my research. I'm also not interested in burning the house down in the quest to save a few bucks. That's the primary directive around here.

What's kind of funny to me is that the guy that was my best man many moons ago is a licensed electrician that I met through work. He could work in any department in the plant and did. Whether it was fixing or installing stuff similar to what we have in our homes to troubleshooting and fixing multi-million dollar machines that had massive amount of electronics and/or computers running them. But he told me that he wouldn't even know where to start on automotive electrics of any kind. You'd think a guy operating at that level would be able to handle that with ease but he said no way, I'd be lost. He's an A/C guy, not a D/C guy and I'm the opposite.

Anyway, I've got a pro coming over to deal with these issues. I made the call this afternoon. I'll have to "supervise" and maybe I'll learn something in the process. I'll never get to apply it but the learning process is still appealing.

 

[momeNt]

Yeah, that's the bigger question and I had a lengthy conversation with a friend of mine that happens to be an electrician about just that subject. All homes met code at the time they were built. What is the extent to which a home needs to be brought up to current standards? My guess is that it is going to vary across the nation. Here at least, there is no municipal inspection process on a home sale. An inspection will occur if the buyer wants one and it is done by whomever the buyer hires. The buyer pays for it too.

Both of my brothers-in-law sold homes within the last few years and the cities they lived in put them through the wringer. A different inspector every visit to inspect that the previous correction was done to their requirements and each new inspector found... something new. The process was nearly never ending. My one BIL's wife was retired from a municipality where she was in charge of payroll. She eventually called people she knew there who called people they knew at the city where their home resided telling them to knock it off. It worked, no more inspections. That's an interesting situation in itself.

I wish I knew the answer to your question because I'd like to know myself but maybe I'll have one before all this is over.

Have you already signed the post inspection amendment?

That request is them negotiating with you. Counter offer, explain the home was built to the proper codes at the time, and see where that gets you. I mean shit, people buy homes with knob and tube still. Sure the inspection will say knob and tube still in use, doesn't mean they ask for it to be replaced.

 

[boomerang]

Have you already signed the post inspection amendment?

That request is them negotiating with you. Counter offer, explain the home was built to the proper codes at the time, and see where that gets you. I mean shit, people buy homes with knob and tube still. Sure the inspection will say knob and tube still in use, doesn't mean they ask for it to be replaced.

No, I haven't signed anything. I am exploring the costs involved to do the work they're asking to have done. And that's the way it was presented, they asked. Formally, in writing but not structured as a demand.

I technically misspoke earlier but I don't expect the costs to be anything I wouldn't be willing to absorb. Out of a long list of items the inspector found, (mostly chickenshit stuff though) the buyer only is concerned about a few items. I think it's best to walk carefully around the hornets nest. Kicking it over isn't in my best interest.

 

[NL5]

If you look at the first reply, it has been a code violation since 1923. So, if your house is older than that, and the panel was installed prior to 1923, you are ok. But, looking at that panel, I can tell it is way newer than 1923. Simple fix, shouldn't be a big deal.

 

[stormkroe]

Every metallic, non-current-carrying part of the system needs to be bonded to ground, that definitely includes sub panels. What has changed is the method allowed to do so (using a neutral conductor as a bond muddies the water, allowing the unbalanced phase load to travel on both the neutral and the bond, which includes those pesky metal parts). The danger here is that a loss of connection somewhere will turn those metal parts into a hot wire, and the electricity will gladly find its way through whatever happens to touch, say, the metal outside of the refrigerator.
As to the other point, while I make a point of forcing fairness out of my inspectors (that's part of my job as the owner of the co.) in your case it's definitely better to tiptoe around the nest. Hell, find out what he drinks and have a bottle there.

 

[NetWareHead]

Regardless of whether this was done correctly or not, I must have an electrician out. I guess I'm wondering whether a pissing match will result if the work has in fact been done correctly. What electrician is going to take the time to put something in writing that refutes what a licensed inspector working for a national inspection company has cited?

Call your electrician and explain what has happened. When I buy properties where the plumbing or electrical are suspect, I pay them to come out and give me a proper inspection.

My last purchase, the home inspector found live knob and tube wiring in the basement. In order to gauge the extent of the wiring, I convinced the seller to allow a secondary electrical inspection, this time with my electrician. We found far more illegal and homeowner repairs than the home inspector did and knocked a few grand off the price of the house as a result. Note that I was not demanding the knob and tube be replaced since the rule is that the house was built to standards of that day and age (house was built in 1890 so of course knob and tube was going to be present). My argument was that knob and tube, although still legal, has outlived its useful life and I was asking for a price reduction on that point.

Since you are the seller, it is a bit different. A buyer can always lose interest in the property and move on to another property to consider. This all comes down to how much do you want to spend on the repair balanced by how badly you want to sell the house. You could choose to fight the buyer with an electrician's note saying the wiring is to spec or is grandfathered in under the correct code applicable to the year of the install. And then compare credentials to see whose opinion carries more authority; the inspector or the electrician. (Most of the time, home inspectors are not licensed master tradesmen.)

IMO, (Im not an electrician), I've learned that all subpanels needed to have isolated grounds and neutral buses. The pic of the subpanel you posted seems to have a shared neutral and ground bus. The neutral wire (with white tape) lands on the bottom screw and connected to the same bus is the green screw which serves as the panel bond to ground. Unless this was code at some point to not isolate these buses, it appears to be wrongly wired.

 

[NetWareHead]

As an aside, I went and bought a GFCI tester and all three of the GFCI's that the inspector said were bad, are in fact good. The TEST and RESET buttons worked fine but the actual tester also shows them to be functioning properly. I now have zero confidence in this inspector the buyer hired. I guess I'm going to find out what kind of battle this is going to turn out to be.

I'd show this to the buyer. Prepare your own refutement of the inspection report complete with pictures. Considering you have both the builtin and external tester backing you up.

 

[boomerang]

Lots of good advice in this thread and I am thankful for all of it.

I was wondering just how long ago it was that the subpanel was installed. Time flies and it seemed like it was maybe 12 to 15 years ago. I dug through my receipts for everything I've had done around the house and I was rather amazed to find that it was put in 25 years ago! Everything I see researching this indicates that the requirements have changed for a subpanel installation.

If this is a cheap fix, I will take the low road. If it's going to be expensive I will probably fight it. One thing I have to keep in mind is that this work, although done to code applicable at the time and by a licensed electrician, was done without a permit. No inspection and no sticker. The home inspector for the buyer made a point of taking a picture of the inspection sticker on the main panel. You can say he covered his ass or was just doing his job or come at that from whatever your perspective may be but he has made a point and one that I get. Plus, I fully understand that the danger present, although unlikely to rear its ugly head, is a possibility.

The receipt I dug up is from the insulation I purchased for the garage. The electrical work was done, I vented the soffits and the roof, then it was insulated and drywalled. The electrician was my friend I mentioned earlier and I am 100% certain I paid him in cash. No paperwork involved. He owned and still owns his own business.

Funny how things can come back to bite you on the ass...