Utility Using Solid Blade Cutout on Neutral

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MichaelCo

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Our utility just provided service to a new construction, and has connected to a pole on our property - I believe the connections are to 21 kv line. The transformer is a pad mount sitting on the property of the new construction. The hot line has a fault tamer cutout, and for some reason they connected the primary neutral via a solid blade cutout. The use of the solid blade cutout requires clearing 10' radius around the pole, which is what prompted my post.
The utility's engineering says that the neutral is required to be fused, not just the primary hot.
This doesn't make sense to me - I can't think of any benefit in fusing the neutral, and can think of undesirables.
Is there a code requirement that specifies fusing the neutral? What fault situations would fusing the neutral handle that the primary hot fuse wouldn't.
 
LarryFine said:
Welcome to the forum.

The NEC does not control power-company installations.
Click to expand...
Is there a good reason to fuse both the hot and neutral? What happens if the neutral opens up, and hot line fuse doesn’t?

Does anyone on this forum have experience with NESC? Thought NESC covers utilities
 
MichaelCo said:
Is there a good reason to fuse both the hot and neutral? What happens if the neutral opens up, and hot line fuse doesn’t?

Does anyone on this forum have experience with NESC? Thought NESC covers utilities
Click to expand...
No, there isn't.

What you suspect.

Some here do.

Correct.
 
Definitely there is a solid blade cutout on the neutral conductor, and a fault tamer cutout on the hot.
 
There were a few things that seemed odd to me. I don't know the purpose of using CN cable for the neutral conductor -should be very close to ground potential. Another odd thing was there is a pole around 10' from the pad mount xformer, yet they ran conduit and wire 250+ feet to one of the poles on our property. There is a pole mounted xformer on that pole feeding another neighbors house, but that would seem a good time to pull that xformer and feed both houses from the new pad mount. There may be something I'm missing, but that would simplify things (one less xformer), and less wire and conduit used.
 
MichaelCo said:
There were a few things that seemed odd to me. I don't know the purpose of using CN cable for the neutral conductor -should be very close to ground potential. Another odd thing was there is a pole around 10' from the pad mount xformer, yet they ran conduit and wire 250+ feet to one of the poles on our property. There is a pole mounted xformer on that pole feeding another neighbors house, but that would seem a good time to pull that xformer and feed both houses from the new pad mount. There may be something I'm missing, but that would simplify things (one less xformer), and less wire and conduit used.
Click to expand...
So again, are you sure it's a neutral? I know the labeling on the pole seems to imply that, but nothing else does. If it is indeed a neutral, perhaps it's unigrounded so the potential Earth could be much higher than an MGn so they treat it like a phase conductor? Not sure, I don't know anything about those and never seen, only heard of.
 
electrofelon said:
So again, are you sure it's a neutral? I know the labeling on the pole seems to imply that, but nothing else does. If it is indeed a neutral, perhaps it's unigrounded so the potential Earth could be much higher than an MGn so they treat it like a phase conductor? Not sure, I don't know anything about those and never seen, only heard of.
Click to expand...
So, I went down to the end of our road, to where the power taps into the main lines. There are 3 conductors at the highest level, and a distance down there is a 4th conductor (not in view in this pic, but will be in next post). This 4th conductor is tied into what is labeled PN on the lines going down our road. The first line at the upper level ties into what is labeled 1 on the lines going to our road.

Our connection to main power.jpg
 
electrofelon said:
So again, are you sure it's a neutral? I know the labeling on the pole seems to imply that, but nothing else does. If it is indeed a neutral, perhaps it's unigrounded so the potential Earth could be much higher than an MGn so they treat it like a phase conductor? Not sure, I don't know anything about those and never seen, only heard of.
Click to expand...
I went down to the next road over, and saw how things were connected feeding power to houses on that road. There were 3 conductors going down that road. One was connected to the same main conductor (1) as on our road, and the additional connected to the 3rd conductor. The last wire was connected to the lower wire, which I would think is the neutral. Now to confuse things a bit, I had to take this picture from the other side of the road (west of the pole), and the one on our road was taken from the east.

I believe our utility power is Wye, but not positive.Next road fed from main power.jpg
 
Hmmm ok, it does seem like there is a neutral then. My guess is it's a wye that is only grounded at the sub, or an ungrounded wye (would they do that???). Like I said before, I don't know much about them, seems like the worst of both worlds to me....
 
electrofelon said:
Hmmm ok, it does seem like there is a neutral then. My guess is it's a wye that is only grounded at the sub, or an ungrounded wye (would they do that???). Like I said before, I don't know much about them, seems like the worst of both worlds to me....
Click to expand...
Still is a head scratcher why they would have a solid blade cutout on the neutral. I looked at around 50 poles in the area, and the only cutout is on the primary hot line. I could imagine a lineman going to isolate the house, and opening up the neutral line without realizing, and potentially surging equipment or humans - The ground rod on the secondary side would help, but still see no reason for to have that cutout. I would think it would be discouraged, or not allowed in the NESC.
 
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