I am doing a car wash job and have a question on bonding the metal structure at the vacuum island. It is about 30 ft. from the service that is mounted on the main building. The raceway is a 2" pvc conduit from the panel to the island. There will be 4ea 120v single phase #10 cu circuits to the island. The bonding jumpers on the main structure are #2 cu per 250:66 (the SEC's are 250kcm cu). My question is this; What size should the bonding jumper from the island structure to the service entrance equipment be? #10 or #2? 250:66 note 2 confuses me. There was no bonding to the re-bar out there. That was all done before I was contracted to do the job.
Bonding of remote steel structure.
- Thread starter bert47
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petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
Re: Bonding of remote steel structure.
It seems to me that this qualifies as a seperate structure. it needs a grounding electrode system.
It seems to me that this qualifies as a seperate structure. it needs a grounding electrode system.
bphgravity
Senior Member
- Location
- Florida
Re: Bonding of remote steel structure.
If you are going to call this vacuum island a separate structure, then you are only permitted to install one feeder or branch circuit to it. You have 4 circuits. That's going to be a problem.
In my opinion, unless the island has a huge canopy with a roof type structure, forget calling it a structure and simply install EGC for each circuit installed in that area, otherwise, you will need to install a single feeder, a disconnecting means, and a grounding electrode system.
If you are going to call this vacuum island a separate structure, then you are only permitted to install one feeder or branch circuit to it. You have 4 circuits. That's going to be a problem.
In my opinion, unless the island has a huge canopy with a roof type structure, forget calling it a structure and simply install EGC for each circuit installed in that area, otherwise, you will need to install a single feeder, a disconnecting means, and a grounding electrode system.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
Re: Bonding of remote steel structure.
how is a pole a seperate structure and not this?
[ June 02, 2005, 09:15 AM: Message edited by: petersonra ]
how is a pole a seperate structure and not this?
[ June 02, 2005, 09:15 AM: Message edited by: petersonra ]
- Location
- Massachusetts
Re: Bonding of remote steel structure.
I am with you Bob, I do not think we really have that option to say it is not a structure.
bphgravity
Senior Member
- Location
- Florida
Re: Bonding of remote steel structure.
Its definetly a structure, but I don't think it is necessary to call it a "separate" structure. I have seen a few car washes that have 8 to 10 little islands for vacuums, shampoo machines, etc.. There must be a least 2 circuits if not more to each one.
Are you saying that is necessary to install grounding electrode systems at each one and only one feeder or branch circuit, and provide a disconnecting means, and, and, and, etc.
I really don't think that is necessary. I would be satisfied with the installation as is as long as the branch circuits are sized and protected properly, with proper equipment bonding, and accessibility to disconnects or receptacles serving the equipment.
Its definetly a structure, but I don't think it is necessary to call it a "separate" structure. I have seen a few car washes that have 8 to 10 little islands for vacuums, shampoo machines, etc.. There must be a least 2 circuits if not more to each one.
Are you saying that is necessary to install grounding electrode systems at each one and only one feeder or branch circuit, and provide a disconnecting means, and, and, and, etc.
I really don't think that is necessary. I would be satisfied with the installation as is as long as the branch circuits are sized and protected properly, with proper equipment bonding, and accessibility to disconnects or receptacles serving the equipment.
- Location
- Massachusetts
Re: Bonding of remote steel structure.
Than IMO it is a separate structure and the NEC requires all that you pointed out.
Did you see my separate structure?
An 8" x 8" pressure treated post with 5 circuits on it.
The local inspector did not see the need for ground rods or a feeder with a panel at the post.
Is it connected to the main structure?
Than IMO it is a separate structure and the NEC requires all that you pointed out.
I agree 100%, I just do not believe with the current NEC wording it is correct.
Did you see my separate structure?
An 8" x 8" pressure treated post with 5 circuits on it.
The local inspector did not see the need for ground rods or a feeder with a panel at the post.
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
Re: Bonding of remote steel structure.
So who's rewriting that sucker, anyway?
So who's rewriting that sucker, anyway?
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
Re: Bonding of remote steel structure.
The OP called it a "remote" structure. That certainly seems to indicate he considers it seperate from the main structure.
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