BONDING A METAL WEATHERHEAD ON OVERHEAD PVC SERVICE.

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petersonra said:
250.92 is a non-starter for this.
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So your interpretation of the word "raceway" in that section is that it only covers the sticks of the raceway itself, and not the fittings that connect them together? If raceway couplings are covered, then the weatherhead at the end of the raceway would be covered.

Also, the internal enclosed volume of a weatherhead looks large enough to me that it could be considered to fit 250.92(A)(2) on enclosures and "meter fittings, boxes, or the like".

Cheers, Wayne
 
I didn’t think a metal gooseneck was listed for use on PVC pipe.
I also thought metal gooseneck was bonded when it was attached to the proper metallic raceway.
 
What exactly would be accomplished by bonding the weatherhead? Please don't say "to comply with code", I would like to know how bonding an isolated metallic object 12' or more feet in the air will help anything.
 
Little Bill said:
What exactly would be accomplished by bonding the weatherhead?
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Practically? It means the fireworks will happen when the first ungrounded conductor faults to it, rather than waiting for two different service conductors to fault to it.

I suppose there are also unlikely situations: around here on residences it's common to have a service riser on the outside of a house up to just under the eaves/soffit, then turn horizontal and stick out past the corner of the house, with a weatherhead on the horizontal section. So an overhead metallic gutter could fall on the weatherhead and get energized if the weatherhead is unbonded and the first fault has already occurred, etc.

Cheers, Wayne
 
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petersonra said:
what OCPD is going to open if a hot service conductor happens to touch the metal weatherhead?
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If the metal weatherhead is bonded to the neutral conductor (or has a fault from a different service conductor)? Either nothing until it burns open, or the utility transformer fuse. Hence the reference to "fireworks".

Cheers, Wayne
 
wwhitney said:
If the metal weatherhead is bonded to the neutral conductor (or has a fault from a different service conductor)? Either nothing until it burns open, or the utility transformer fuse. Hence the reference to "fireworks".

Cheers, Wayne
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Wouldn't it be safer to not bond it then?
 
petersonra said:
Wouldn't it be safer to not bond it then?
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Depends on whether you think the (possible) state of being energized and isolated is safe enough, or if the risk of it then energizing something else is high enough you'd rather have it go boom at the first fault. Clearly everywhere downstream the latter is the choice.

Cheers, Wayne
 
wwhitney said:
Depends on whether you think the (possible) state of being energized and isolated is safe enough, or if the risk of it then energizing something else is high enough you'd rather have it go boom at the first fault. Clearly everywhere downstream the latter is the choice.

Cheers, Wayne
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once it gets to a reliable OCPD bonding makes a lot of sense but on service wires where the chance of it opening an OCPD upstream is remote...

seems to me it is a fire hazard.
 
I'm worn out just reading the thread...seems like a case of use a PVC head on a PVC mast or metal head on metal conduit and then none of this matters :)
 
Although it is specifically talking about an EGC I see 250.110 (1) saying it is not necessary to be bonded.

And I'm sticking to it. ;)
 
Jpflex said:
Anything likely to become energized?
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I don't see how it's likely to become energized. You would have to have both a failure of the wire insulation plus a failure of the insulation surrounding where the conductor actually enters the weather head to have an energized weatherhead. I suppose it could happen but it's pretty unlikely.
 
petersonra said:
I don't see how it's likely to become energized. You would have to have both a failure of the wire insulation plus a failure of the insulation surrounding where the conductor actually enters the weather head to have an energized weatherhead. I suppose it could happen but it's pretty unlikely.
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No code just says anything likely or can potentially be energized must be bonded
 
You could stick a lug onto the clamp screw at the neck of the weatherhead where it slides over the pipe. Bring the bonding conductor thru the weatherhead and loop it back to the lug . Bond the other end inside the meter can. Cut and dry.

When we start out with pvc and then transition using couplings to GRC on some service drops due to POCO not allowing any PVC conduit to be part of the thru the roof mast head, we do the same almost. In that case we have GRC pipe so a large water pipe clamp goes onto the GRC just below the mast head , and I run the bonding conductor (which is only run in cases where we are going from pvc to rigid steel conduits for a mast)
to the water pipe grounding clamp and secure it into the proper clamping screw hole . Expensive hassle nowadays but PVC is a hell of a lot cheaper than Galvanized Rigid Steel Conduit so sometimes only the last ten feet of a long running service drop is in GRC, even though I have to run an extra bonding conductor thru the conduit along with the service drop conductors. And buy a big water pipe clamp as well.
 
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