Spot the violation(s) Texas

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e57 said:
This is where we differ - especially since we are under the same POCO (PG&E) who rarely installs an electrode at any pole mounted transformer location. (If it weren't raining right now - I would say go outside and take a look.) They are often fully dependant on local grounding at each service for overhead installations via the grounded service conductor. (A means of grounding that is dependant on the service itself being grounded - along with the many others on the system.) The idea the SE conductors would not be involved during a lighting event, even outside of that particular arrangement described, ignores the fact the all available paths would be taken by the current involved in a lightning strike.
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OK, you have a good point that I missed. The metallic service conduit contains a conductor that may be carrying a lightning induced pulse to earth.

So here's a question, if you have a metallic service riser, is it bonded to the neutral at both ends, or just at the meter base? [I honestly don't know, we have an underground service and I've not done any service work.] If the service riser is bonded at only one end, it will be a "choke" for its entire length. In that case, the small amount of service conduit between the meter base and the separate main disconnect would be of secondary importance.

Cheers, Wayne
 
220/221 said:
If you are mounting the meter and panel outside you are wasting time/money doing it this way.

Tell your boss that all in one, 40 space meter/main/panels are like $120 :cool:

Mount one box and you are done. It's been standard practice here since 1970 something.
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AKA "Slapper" - slap it up and you're done.
 
wwhitney said:
If the service riser is bonded at only one end, it will be a "choke" for its entire length. In that case, the small amount of service conduit between the meter base and the separate main disconnect would be of secondary importance.

Cheers, Wayne
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True..... Hmmmmm..... But any path for be it lightning or fault current will be through that section of conduit between the meter and main. Even though it is a paralel path(IMO especially since it is) for neutral current - there should be little chance for there to be two potentials, and bonding only one end may allow there to be - depending on the capacity of the neutral - which is acting as a link between to main bonding jumpers.

It makes no sense to me why they removed that wording in the 08 code - especially since we are only talking about a single meter and main - that type of service conduit is very common on multi-unit metering with several main disco's, where that path may be more crucial. Technically, as for the bonding at end of service conduit - I'm not even sure that was Mike Holt's intent in writing/deleting it - or if the current wording changes the installation - depends on interpetation IMO.

My interpetation - since 250.92B is still in place - that the wording of 250.92A "electrical continuity" and 'B' regular lock-nuts are not OK would still mean bonded at both ends....
 
e57 said:
My interpetation - since 250.92B is still in place - that the wording of 250.92A "electrical continuity" and 'B' regular lock-nuts are not OK would still mean bonded at both ends....
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So I take it you bond the top end of the riser?

I agree entirely with Rob here.
 
iwire said:
So I take it you bond the top end of the riser?

I agree entirely with Rob here.
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No, it is a good point though.

But do you see my point that you could have two or more enclosures at different potentials based on the neutral current in each in a multiple main setting?
 
If there is a Fault in the Panel, It should go through the Bonding screw, to the Neutral,then back to the source. If there is a Fault in the meter it should go back to the source through the neutral since the neutral is bonded to the Meter Can.
That leaves us with if there is a fault in the offset nipple where does it go.
I would say that if all of the concentrics are out then no additional bonding is required. The Bonding jumper on one end of the offset nipple would direct the fault to either the Panel neutral or the meter neutral.I would think the Bonding jumper in this case (if installed) would be an assured bonding jumper.(Nothing wrong with that but is it actually required).Also the Choke only applies when only the Grounding conductor is installed in a ferrous raceway, which is not the case here.
 
jap said:
That leaves us with if there is a fault in the offset nipple where does it go.
I would say that if all of the concentrics are out then no additional bonding is required. The Bonding jumper on one end of the offset nipple would direct the fault to either the Panel neutral or the meter neutral.
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It would take BOTH. It is still a metalic path to both. i.e. all paths not the path of least resistance.....
 
Bob, and Rob

In your minds eye - cut the neutral in the main panel....

For that matter just think about neutral current in the that way those panels are set up now - one dependable low resistance path on the neutral - the other a varied path dependant on that nipple.
 
Thats true, so what would you be doing installing a bonding jumper on one end of the nipple? Just assuring a bond, not directing it. So is the offset nipple considered sufficiently bonded if all of the concentrics are removed or not? Because if it is, there is no need for the bonding jumper.

Please let me know if I'm completely wrong here.
I have never seen a bonding jumper on either end of an offset nipple in an installation like this where all of the concentrics were removed.
 
Mark, all we have to do is ensure each of the service raceways and enclosures are directly connected to the grounded conductor. This can be done from one end only.


Do both ends if it pleases you but it is not NEC required. :smile:
 
The way I see it - the nipple (if metalic) is carrying current - I'll bond it! Both sides - as that current is not going to come back to go some way I think it might go - it is going to go back to it's source on both paths - the neutral and the conduit/nipple.

The NEC assumes it is the sole source of rules when it applies to service equipment, and assumes that there will only be one MBJ, when there is often another in the metering equipment. If you are to bond one end of the conduit to the grounded conductor - which one? The one in the main, or the one in the metering the NEC chooses to ignore - I say both.

My only regret is that I failed to see this back when proposals were due for the 2011 cycle.
 
i am understanding bonding is very inportant if some how the grounded conducter becomes lose on the service side a parael circuit could act in series and the load side phase with the higher impedance will draw a higher voltage bye bye flat screen
 
This is a terrible install. What part of Texas is this? I started my career in
Houston TX and a install like this would of never passed inspection. Granted
I only did 4 houses during my apprenticeship.
 
220/221 said:
Tell your boss that all in one, 40 space meter/main/panels are like $120 :cool:

Mount one box and you are done. It's been standard practice here since 1970 something.
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I'm sure they would be doing that if the poco approved all-in-ones there. Perhaps they don't.
 
Karl H said:
This is a terrible install. What part of Texas is this? I started my career in
Houston TX and a install like this would of never passed inspection. Granted
I only did 4 houses during my apprenticeship.
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This is in Bryan TX

It has not got an inspection yet. We still have 2 smokes to install. I wait to see if it passes.
 
I still believe that if all the concentrics are taken out that this offset nipple is considered bonded already and no jumpers are required.
Am I wrong in assuming that?
 
peter d said:
I'm sure they would be doing that if the poco approved all-in-ones there. Perhaps they don't.
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I had never even seen a "All-In-One" until I moved to California.
In Texas is was always a seperate meter can. BTW meter cans were free
from the POCO. All you had to provide to the POCO for a free meter
can was an address.
 
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