Overhead service guy wire neutral question?

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  #1  
Old 05-01-15, 12:20 PM
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Overhead service guy wire neutral question?

I have overhead service to the house.

The triplex has a bare neutral/ground wire. Evident from the green oxidation on the wire.

The neutral appears to act as the guy wire as well. I see it connected to the clamp on my riser and also clamped to one of those insulated clamps at the pole.

Is it typical for the third wire of the triplex (ground) to be used as the support as well?
 
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Old 05-01-15, 12:46 PM
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The uninsulated wire is called a messenger and is not a ground. It is the grounded conductor from the center tap of the service transformer. secondary. The grounded conductor is informally called the neutral. The two insulated wires are two 240 volt ungrounded legs of the service transformer secondary.

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Old 05-01-15, 01:14 PM
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The bare conductor of the overhead triplex is called ACSR for Aluminum Conductor Steel Reinforced. The steel provides the strength to support the cable.

ACSR
 
  #4  
Old 05-01-15, 01:19 PM
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Im not certain the bare "messenger" wire would be ACSR alum. since it has oxidized green.

Unless the exterior is the steel... but I am not sure that steel turns green.
 
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Old 05-01-15, 02:22 PM
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Is it green where it connects to the house drop ?
Possibly your service is copper and water is running down it onto the messenger.

It would be extremely rare to see a copper drop and even rarer a bare copper neutral messenger.
 
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Old 05-01-15, 03:43 PM
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A pure copper messenger would not have the needed strength. Among other things it would gradually stretch. Pure aluminum will also stretch, and more so than copper.

The messenger is tied to (bonded to) the ground wire that goes from pole to pole and which also has the job of carrying neutral current to other service lines tapped off from different utility poles.

The pole to pole ground/neutral has grounding electrode conductors to rods at the bases of some if not all poles.

A "guy" wire goes from somewhere up on the pole down to an anchor on the ground. It could conceivably be a grounding electrode conductor but I do not think this is a customary secondary role. A guy wire holds the pole upright (or sometimes at a desired angle) requiring a lot of tensile strength, while a messenger wire's role is to support wires that accompany it.
 

Last edited by AllanJ; 05-01-15 at 04:07 PM.
  #7  
Old 05-01-15, 04:26 PM
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Its certainely isn't the braided aluminum I see in the photos when googling ACSR. Its an old installation..... which connects to my new service (so the poco made the crimps just last year).

It appears to be a solid conductor, probably #8 or #6... cant tell from ground level. It does have green ox on it.

If it is copper, perhaps its uncommon as you suggest in your area and not here? (Chicagoland)... perhaps its a regional thing....

p.s.- this is the power co. equipment ... I took a walk this evening and see similar if not exactly the same setup on the other transformers down my block. So I must be missing something here in regards to oxidation on the bare conductor/support.
 

Last edited by zmike; 05-01-15 at 04:51 PM.
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Old 05-01-15, 05:20 PM
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Please post a picture. .
 
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Old 05-01-15, 06:44 PM
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It appears to be a solid conductor, probably #8 or #6... cant tell from ground level. It does have green ox on it.
That sounds like an older copper service drop and it wouldn't be triplex, but three separate strands. You don't see these much any more except in older areas with services that have not been upgraded. The green oxidation and also that it is a solid conductor is the giveaway that it is copper.
 
  #10  
Old 05-02-15, 04:17 AM
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That sounds like an older copper service drop and it wouldn't be triplex, but three separate strands. You don't see these much any more except in older areas with services that have not been upgraded. The green oxidation and also that it is a solid conductor is the giveaway that it is copper.
Yes, I didnt realize "triplex" is a different animal all together. This is indeed in a very old area.

When I updated my service last year, should I have expected the poco to change the drop as well?

With these old copper service drops, is it incorrect to have the messenger wire in this case used as the support as well?

Since this is the poco property, should I make an issue out of having this old drop replaced? If they put it up to begin with, can I assume its correct, safe and functional?

Thanks for allowing me to ask my questions here.
 
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Old 05-02-15, 05:35 AM
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I would leave it in place, assuming that the connections at the ends are sound and the messenger has not stretched to the point where any of the connections to any of the wires seem to be pulling apart.

Typically the messenger is anchored directly to the pole or to the house with clamped on jumper wires (bonding wires) at each end and with some slack to provide the neutral function of the messenger. We have seen service drops with the service messenger clamped to the pole to pole messenger (with secondary hot conductors wrapped around it) or sometimes a single pole to pole ground/neutral in between poles.
 

Last edited by AllanJ; 05-02-15 at 06:06 AM.
  #12  
Old 05-02-15, 06:46 PM
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When I updated my service last year, should I have expected the poco to change the drop as well?

With these old copper service drops, is it incorrect to have the messenger wire in this case used as the support as well?
It isn't necessary to replace the older copper drops just because you update your service, the drops are sized according to actual load and not the size of your service. Actually, the copper drop is generally better than an aluminum triplex drop. There is no messenger on these old drops, each conductor is a solid conductor and supports itself.
 
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Old 05-02-15, 08:34 PM
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But the O/P in the first post said it was triplex. That looks nothing like the old copper drops and weren't the neutrals on old copper drops insulated? (Only familiar with 120 drops but I'm positive both wires were insulated.)
 
  #14  
Old 05-03-15, 06:30 AM
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Common 70 or so years ago and still seen occasionally is the open secondary. Each of the lines (two hots and neutral for 120/240 volts) is hung separately going from pole to pole perhaps about 6 inches apart and is anchored to its own insulator on the side of the pole about halfway up. Similarly, the service consists of three separate (single conductor) lines to the house. None of them are bare.

This has gone out of style for a variety of reasons including being less attractive looking than a single line with the conductors wrapped together or in the same cable sheath.
 
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Old 05-03-15, 06:36 AM
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Looking back at the first post again, you have a good point, Ray.

The triplex has a bare neutral/ground wire. Evident from the green oxidation on the wire.

The neutral appears to act as the guy wire as well. I see it connected to the clamp on my riser and also clamped to one of those insulated clamps at the pole.
Copper triplex may have been available back in the day, but I don't think it can even be special ordered today (or for the last 30 years). Some pictures would be helpful.
 
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