Detached garage sub panel question

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Situation is: A residential home with a detached garage has a sub panel which is serviced from a 50A breaker located in the main breaker box. This service feed is approximately 20'. The house has a meter pan/disconnect where the 200A service enters the house. The breaker box is approximately 30' from the meter pan. There is a grounding rod, earthed at the meter pan entrance which goes to the breaker panel. The water lines are bonded. My main question is should the sub panel in the garage be earthed or do I use the ground wire from the main to act as my safety ground like to carry currents from a lightning strike to the original earthed point all the way across the house by the meter pan.
Since the garage is detached, wouldn't I want to provide a path for lightning to the closest point?
Any advice will be appreciated. :-) Thank you
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If the feeder to the garage is 4 wire, the grounds and neutrals at the garage should be on separate busses, and a ground rod or two should be driven at the garage and attached to the grounding detail. If there is only three conductors in the feeder from the house, the neutral and ground busses should be bonded together in the garage panel, and a ground rod or two should be driven and attached to the neutral - ground detail
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The 2008 code eliminated the 3 wire feeder entirely. You have to go the 4 wire route described above.
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On Jun 14, 9:36 pm, snipped-for-privacy@aol.com wrote:

Yep, rule is if he touches it then it needs to be up to current code. It should have 4 wires. The ground and neutral miust be on isolated form each other on different buss bars. There needs to be 2 ground rods.
On the other hand if all he has is a 3 wire setup already installed with no ground at the building and he's just looking to make it safer then he could add a ground rod or two at the garage. But don't get it inspected.
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No that is not the rule unless the authority having jurisdiction is abusing her/his authority. Once that feeder is installed and accepted by the AHJ it is good for the life of the structure unless more then a certain percentage of the structure is remodeled under a single permit. A Grounding Electrode System has always been required at detached structures so if yours does not have one then it should not have passed it's initial inspection.
To answer the original posters question if there is not already a Grounding Electrode System at the detached structure it would be a very good idea to install one. -- Tom Horne
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This is not a new installation. It's existing, and the op doesn't say if it's 3 or 4 wire. He didn't ask how a new installation should be done.
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My bad, sorry. You are right about the rod.
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On Jun 15, 12:48 am, snipped-for-privacy@aol.com wrote:

Don't get me wrong I'm not against just adding a rod. But I thought if you work on an area of your system that it then needs to be brought up to current code?
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RBM wrote:

Thanks to all who responded, your advice is greatly appreciated
It is existing, using a three wire feed. I am installing additional electrical circuits off of this sub in the garage need to get it inspected. Once the inspector opens the panel I am afraid he will make me comply with the 2008 rule change. I am not sure if it is grand-fathered.
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If it was done legally to begin with, it should have had ground rods already . There is no reason the inspector should have a problem with it since it was done before the code change.
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Best solution is to cal him now and explain what you have. Ask him what he'll accept. It should not have passed inspection before but that's not your fault. How's the wire run between the house and garage now, overhead? Or buried? If it's buried maybe you should ask him out to look at it and that might help your case if he sees it will be a pain to change.
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Boy things must work differently where some of you are from. My experience has been that as a homeowner you can get an inspector to answer some questions, but even then, it better be a direct code related question, not an open ended, what;s the best way to do this one. And as for a field visit, forget that without a permit and then only for inspection.
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On Jun 16, 9:41 am, snipped-for-privacy@optonline.net wrote:

That might be. If he's not willing to come out then take a few pictures and go visit him. He's eventually going to have to inspect it. It's actually in his interest for you to ask enough questions so that what you do satisfies him. Otherwise he's just going to have to make repeat visits and possibly going to piss you off. While you're not likely to win any actual concessions from his management they still do not like to hear from complaining citizens. At the end of the day they do work for you. I don't see a downside to trying to work with the guy up front to avoid problems later. If he blows you off and then decides he has problems with your job you really do have a valid complain then.
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That might be. If he's not willing to come out then take a few pictures and go visit him. He's eventually going to have to inspect it. It's actually in his interest for you to ask enough questions so that what you do satisfies him. Otherwise he's just going to have to make repeat visits and possibly going to piss you off. While you're not likely to win any actual concessions from his management they still do not like to hear from complaining citizens. At the end of the day they do work for you. I don't see a downside to trying to work with the guy up front to avoid problems later. If he blows you off and then decides he has problems with your job you really do have a valid complain then.
Clearly electrical inspection is different by location. In downstate NY, inspection is done by private certified electrical inspection companies. The only helpful information they'd be likely to give a homeowner is to call a licensed electrician. Many are unlikely to give licensed electricians any advice other than regarding subjective gray areas, and they could care less how many trips they have to make to a job, as we have to pay them for each one
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jamesgangnc wrote:

Very true. I just want to educate myself on what to expect so I could intelligently talk to the inspector about the potential problems we might encounter. As suggested, I am going to visit him tomorrow with some photos. I'll keep the group updated.
Again, thanks for all the valuable insight and wisdom provided.
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Ed B wrote:

Update, spoke with the inspector. He has told me the panel and feed is grandfathered therefore no rod required. Thanks again for all the sound advice
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WHAT ABOUT THE GRANDKIDS AND THE FACT THAT YOU ARE SAFELY GROUNDED ALREADY DID HE EVEN MENTION THEM [;-)]
GLAD WE COULD HELP
I AM PROTEUS
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A reasonable man. Good news. That will make your project much simpler.
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jamesgangnc wrote:

Why shouldn't it have passed?
If it is because it was 3 wire with no ground wire, as several people have already said that was allowed prior to the 2008 NEC.
And it is explicitly grandfathered in the 2008 NEC: "250.32-B-Exception: For existing premises wiring systems only, the grounded conductor [neutral] run with the supply to the building or structure shall be permitted to be connected to the building or structure disconnecting means and to the grounding electrode(s) and shall be used for grounding or bonding of equipment, structures, or frames required to be grounded or bonded where all the requirements of (1), (2) and (3) are met:" (1) there is no ground wire from the source (2) there are no metallic paths bonded to the grounding system [like metal gas pipe] (3) ground fault protection is not installed at the source of the feeders And there are requirements on the size of the neutral - if it is the same size as the hot conductors it complies. end 250.32
There should have been a grounding electrode in the original installation (these days typically 2 ground rods, in the good old days I think you could use 1).
--
bud--

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The OP hasn't specified, but since he seems sure that there are no rods, I wonder if the feeder isn't in metallic pipe.
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