No ground at garage sub panel

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Thanks all. Seems like I stirred up an old argument.

Anyway, it is going to be inspected in Kentucky under 2005 code. A permit was pulled by our company, but not by the previous company that started this mess. I?m not sure how the inspector got involved before we got the job, but he sure is POed at the last guy and took pictures of the bad install and such. It is a new garage with a second floor studio and maybe a building permit flagged the guy for not pulling an electric permit.

I called my boss tonight and he said the inspector told him to separate the grounds and neutrals at the garage panel and not connect the neutral to ground. My boss said he didn?t think that was right. That would be fine if he had a continuous ground from the house. I will get out my 2005 code tomorrow and get the code references and since I am a NFPA member, I might even get a code interpretation in writing via email to help explain to the inspector that the ground and neutral need to be bonded at the garage panel.

I don?t read the forums here much but I did sign up a couple years ago. From the replies I got this time, I think I could really get some good help here and stir up some trouble from time to time. Thanks all and take care!
 
brian john said:
Rick you have proved nothing until you.

1. Megger all branch circuit neutrals to prove there is no contributing factors from downstream shorts on neutrals to your current on the water line.
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This would have no bearing on the situation. Even if there was a dead-short from neutral to ground downstream, it would be nevertheless be downstream from the main load center's neutral-ground bond. The main bond at the load center "trumps" all illicit or intentional bonds elsewhere within the house.
brian john said:
2. Are sure your neighbors are even connected to you through the water lines or at the transformer.
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No, but wasn't that the primary premise that began this discussion? However, in all likelihood we are all connected together because this area for the time period used copper lines from the houses to the mains, and the same builder (a friend of mine) built all of the houses. I watched mine being installed, and it was a standard saddle on the main line with copper running to the water main near my panel.

However, I think you completely missed the point. The discussion began (either here or in the other thread) that current in the grounding system (GEC and/or water line) was due in whole or in part to a ground loop with the POCO ground at the transformer. The opposition to this stated that it was due to what I have termed a Super Neutral.

I never stated that my test disproved the possibility of a super neutral, but it did in fact prove that in my instance there is no super neutral, and all of the current in my GEC (which has been recorded as high as 14 amps in the past) is in fact due to a ground loop.
 
This would have no bearing on the situation. Even if there was a dead-short from neutral to ground downstream, it would be nevertheless be downstream from the main load center's neutral-ground bond. The main bond at the load center "trumps" all illicit or intentional bonds elsewhere within the house.
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One source of ground current in addition to the common transformer/water pipe issue are downstream grounds on the neutral, how do you say a bond in the panel trumps these?

However, I think you completely missed the point. The discussion began (either here or in the other thread) that current in the grounding system (GEC and/or water line) was due in whole or in part to a ground loop with the POCO ground at the transformer. The opposition to this stated that it was due to what I have termed a Super Neutral.
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Actually I think YOU were the only one leading this charge. What I stated was in my expierence large measurements of ground current can be traced to several causes.

1. Down stream grounds on the neutrals
2. Metallic connections between the utility transformers and the facility with a grounded service.
3. The common transformer and utility water pipe issue.
4. And not mentioned some leakage current depending on age of the system, size of the system and loads served.


I did not say your SUPER NEUTRAL does not exist (actually it does it is a Copy Righted term for Allieds cable http://www.alliedeg.com/SuperNeutralCable_1591.asp) I said in my exopierence in trouble shooting ground current it is not an issue I have seen.
 
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dhalleron said:
Thanks all. Seems like I stirred up an old argument.
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No, there isn't any sort of argument. It is just a challenging discussion. If it wasn't for these challenging discussions every once in a while, life would be pretty boring here, and virtually every question could be answered with a reference to code or past question.
 
Ran out of editing time.

I do not have the luxury of a common water pipe or transformer to check this out. But looking for further insight. So other members get the amp clamps out.
 
brian john said:
One source of ground current in addition to the common transformer/water pipe issue are downsteam grounds on the neutral, how do you say a bond in the panel trumps these?

It is a path for current, bonding in your panel is not some magical way to avoid downstream grounds.
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I want to make sure there is no confusion in terminology. "Downstream" means stuff inside the house after the bonding of the main load center. "Upstream" would indicate POCO for sure, but possibly include the meter socket, etc.

So if you truly do mean to say "downstream", then yes, absolutely, the main bond "trumps" all other downstream bonds whether they are intentional or not. You could have a billion downstream bonds, and it would not impact how current flows in the GEC upstream from the main bond.

If you were referring to an upstream bond, I installed the service in this house from the transformer vault, through the meter socket, and to the load center. There are no bonds, and if there is any leakage, it can only be to dirt/ground, and cannot be to any portion of my grounding electrode system.

Edit By the way, I was apparently writing this while you were editing your previous posting that I had already quoted.
 
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A not so easy but compliant 3rd way

A not so easy but compliant 3rd way

dhalleron said:
Thanks all. Seems like I stirred up an old argument.

It is a new garage with a second floor studio and maybe a building permit flagged the guy for not pulling an electric permit.

I called my boss tonight and he said the inspector told him to separate the grounds and neutrals at the garage panel and not connect the neutral to ground. My boss said he didn’t think that was right.
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First up, it matters what the local AHJ delegates and getting a reading from the building department is the main issue. Liability falls on the GC or the owner who pulled the original project permit. In either case, the 4-wire stands according to the above data.

Looks like a concrete saw for open trenchwork between the building looks immanent. Do a neat job, then back-fill the sidewalk path with designer pavers to look like it was done on purpose. The USE into the house is also part of the violation and needs to be corrected if the AHJ requires getting the 4-wire into the panel. That is the hard part.

Where is the panel located in respect to the USE entry? (Hopefully at the point of entry where a sweep can be installed after sawing into to garage slab and the wall or installing a back-to-back outside feedthrough or disconnect box.)

Additionally, the UFER footer would have been present if UBC and IRC codes were followed when the project started. Sounds like this is unfortunate for everyone involved. It all comes down to the inspector following the local rules though. That is the real answer. rbj
 
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In ?2008? 250.32 was revised to eliminate parallel neutral current on non-current carrying items, neutral current is not allowed on anything other than an intended conductor. This enables 250.24(5) & 250.142(B) compliances. Fault current is supposed have an intentional path to source (not earth) and the neutrals are not supposed to bond past the service disconnect if they cause a parallel path.
 
250.32

250.32

tryinghard said:
In ‘2008’ 250.32 was revised to eliminate parallel neutral current on non-current carrying items, neutral current is not allowed on anything other than an intended conductor. This enables 250.24(5) & 250.142(B) compliances. Fault current is supposed have an intentional path to source (not earth) and the neutrals are not supposed to bond past the service disconnect if they cause a parallel path.
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I agree. Your comment is the main point. With a metal h20 pipe and a four wire sub fed from the main building , there would be a separate continuous bonded pipe to the new building. rbj
 
gndrod said:
I agree. Your comment is the main point. With a metal h20 pipe and a four wire sub fed from the main building , there would be a separate continuous bonded pipe to the new building. rbj
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Which is exactly how 8 bazillion services are here in the USA so I really do not understand the need for the change.

As Don and I like to joke about 'Do electrons behave differently on each side of the service disconnecting means?'
 
Update

Update

My boss figured out the right way to do it with my help and yours and the inspector was ok with it after he was given the code quote. Bonded the neutral and ground at the garage and all is well.

He even found another screw up from the previous electrician. There was a combo cook top/fridge/sink that needed a neutral, but the guy ran a 2 wire with ground and used the ground as a neutral. It didn't work very well when the only ground was the driven ground not bonded to the neutral. That wire is going to be replaced with the right stuff.

Thanks all!

Dale
 
dhalleron said:
...There was a combo cook top/fridge/sink that needed a neutral, but the guy ran a 2 wire with ground and used the ground as a neutral. It didn't work very well when the only ground was the driven ground not bonded to the neutral. That wire is going to be replaced with the right stuff.

Thanks all!

Dale
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This appliance may not be a good example but ovens, ranges, dryers, and such used to be allowed on a 3 wire circuit '96' and later if I remember correctly. Now 250.140 requires 4 wire (single phase).
 
No ground at garage sub panel

I want to apologize if this is not a part of this installation --but I just wanted to make sure--"Is there by any chance a pool with its associated equipment ,being fed from this sub panel out there in the garage"?
I only ask because it is reminiscent of an oft repeated and after the fact discovered mistake found when being called in for an after the fact pool install done by others[not the filing electrician even thoough that electrician is taking responsibility/liability for the install]
 
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