bonding to ground correctly

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electricalist

electricalist

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dallas tx
Meter 2"" ridged nipple to panel bonding bushing in panel, ground is a egc? If the conduit can be a ground can from the bonding bushing to the main panels ground / neutral bus be just a jumper? If the ground is correct for size?. In odessa the meter must be bonded by egc. . In dallas they will not connect power if there is any conductor (ground ) landed at the neutral. It seems that at the main panel there is a bond that will include the meter if assembled correctly. Odessa requires an actual wire. This to me seems like a parallel path for neutral. From main panel back to meter on neutral then again on ground. Is this electrical corruption?
 
There is no EGC on the line side of the service disconnect, in your example you would have a metallic service raceway (2" nipple) which is required to be connected by something other than standard locknuts so a bonding bushing can be used with a bonding jumper to the neutral bus. As Dave stated look in 250.92(B).
 
infinity said:
There is no EGC on the line side of the service disconnect, in your example you would have a metallic service raceway (2" nipple) which is required to be connected by something other than standard locknuts so a bonding bushing can be used with a bonding jumper to the neutral bus. As Dave stated look in 250.92(B).
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Thats how I understood it to and I do it. In odessa we met with the inspector before hand to ask some things he mentioned a code reference I dont remember off my head stating meterbases and the like must be bonded. I said im pretty sure it is by the method of connection and a bonding bushing. They require the actual conductor to land in the meter base under grounding screw on small meterbases and mechanical lugs on transocket. Foolishly I ask is the a neutral parallel. Understanding the neutral load will take both paths when parallel. Actually as yal stated that occurs weather by wire or bonding
 
I am about to say something foolish ...... if the parallel of neutral is a bad idea . I belive so then I wonder why the meterbase is not considered the first means if disconnect and n/g bonds be msde there only or in our first means and no bond for poco/customer shared meter base. . The meter base does disconnect first after transformer. So its a separately derived sysyem begening at the meter just asking
 
If the wiring method were PVC or SE cable then an unbonded neutral in the meter enclosure would allow the enclosure to possible become energized without anyone knowing about it.
 
Yes sir that is true and im am learning. If the load on the neutral devides onto each path as in half on sized neutral half on bonding back to meter would it not devide by 3 if an inspector insisted on on an actual grounding conductor? If so then id think any bond would need to be capable of the full load incase one of the others were lifted if that makes sense
 
electricalist said:
I am about to say something foolish ...... if the parallel of neutral is a bad idea . I belive so then I wonder why the meterbase is not considered the first means if disconnect and n/g bonds be msde there only or in our first means and no bond for poco/customer shared meter base. . The meter base does disconnect first after transformer. So its a separately derived sysyem begening at the meter just asking
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A meter socket is not a disconnect per NEC. An enclosure that contains both a meter and a fused switch or circuit breaker would have to be considered the service disconnecting means though and the load conductors would be branch circuits or feeders.

Your typical single meter socket has the grounded conductor terminals bonded to the enclosure - no additional bonding jumpers are necessary for bonding the enclosure, but you may need a bonding jumper for a metallic raceway leaving the enclosure.
Such raceway should only need bonded at one point an not necessarily at both ends like some people think it does.
 
Yes sir I sgree. Isee bonding bushings at both ends snd all kinds of other pointless places that dont require them. If I rework something they go in my truck if not required. So is it a parallel patg for neutral from 1st disc. Back to meter and adding a actual wire as well devide it more . If so could this be problematical in theory
 
electricalist said:
Yes sir I sgree. Isee bonding bushings at both ends snd all kinds of other pointless places that dont require them. If I rework something they go in my truck if not required. So is it a parallel patg for neutral from 1st disc. Back to meter and adding a actual wire as well devide it more . If so could this be problematical in theory
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All metallic enclosures containing service conductors are required to be bonded to the grounded service conductor. Most typical applications is from a meter to a service disconnecting means, but there are other instances of such parallel paths. NEC doesn't really address this as an objectionable current path though. The bonding jumper to the raceway is not because of parallel current paths it is to ensure the metallic raceway is bonded to the grounded conductor.
 
Yep I get when bonding bushing are required. I spent a month reading codes talking to ec and analizing every system I could . My parallel question is not about the bond I know irs the to activate ocp during a fault and a ground rod will most often not work for that to happen.. reading on the need for isolating them after first disconnect I thought it said it was to avoid backfeeding and energizing the the grounding system and to avoid a parallel path back to source
 
electricalist said:
My parallel question is not about the bond I know irs the to activate ocp during a fault and a ground rod will most often not work for that to happen..
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My point was because it is required to be bonded to the grounded conductor it inherently will be parallel to the grounded conductor, not much you can do about it if it is required to be bonded at every enclosure on supply side of service disconnecing means, aside from using non metallic raceway or cable sheaths.

Also keep in mind we are talking service conductors and equipment - there is no overcurrent protection to activate, the second part of what you mentioned there is the purpose of the equipment grounding conductors after the service disconnect or after a separately derived system, there is no EGC with services everything is bonded to the grounded conductor which can be carrying current under normal operation.
 
electricalist said:
I see and ty for re explaining im learning what I can as well as why which really help when im there looking at work
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I'm glad you are interested in the why part. That generally makes things easier to understand, also comes in handy when troubleshooting problems to know the why part.

There are many out there that learn how to install but when it doesn't work they don't know how to find out what is wrong partly because they don't really know how or why it works in the first place.
 
I worked on custom houses for years and its fundamentally basic til we need to understand and explain lutron systems why a florescent wouldnt dim . Being able to call the office and this is what the customer needs. Then tell the customer and I know first hand these customers will trust you in ways are profitable affordable and dependable. In commercial never any disrespect to those who can do it but dont know why. Thats not me I have to understand it believe in it and know it well enough to explain so that a customer a busy boss a helper or a co worker can understand. Yes I hate when someone gives an answer that sounds like right. But not even close
 
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