Cable Hanger Clamps VS. Messenger Wrapping

[BlackBooker]

I have noticed that the power utilities overhead service feeders after the transformers are attached differently to the screw-in insulators on the pole. I noticed that instead of using a hanger clamp on the messenger wire, they instead separate the messenger wire from the bare wire on the tri-plex, pass thru the insulator & then wrap tightly around the bare wire on the tri-plex. Which is better & are we allowed to do the same with our overhead services?

--David

 

[charlie]

WOW! I would love to answer that question but I don't know what you are talking about. Electric utilities all have access to the same material but decide which materials they wish to stock and use for each situation. In addition, the linemen are very intelligent and will come up with their own ideas and submit them to the standards committees for consideration.

We use parallel cable (bare neutral with two phase conductors that are lashed together in parallel) that is clamped to the poles. The triplex service drops are attached with service grips (Chinese handcuffs - sort of) on either end. We do not attach anything that is just screwed into the poles, everything is attached to 5/8" through bolts.

You can do anything on the poles that you wish as long as it is safe and "approved". :smile:

 

[LarryFine]

I noticed that instead of using a hanger clamp on the messenger wire, they instead separate the messenger wire from the bare wire on the tri-plex, pass thru the insulator & then wrap tightly around the bare wire on the tri-plex.

I've always believed that the messenger IS the bare wire, ACSR*.


*(Aluminum Conductor, Steel Reinforced)

 

[charlie]

I've always believed that the messenger IS the bare wire, ACSR*.

*(Aluminum Conductor, Steel Reinforced)

For what it is worth, most electric utilities no longer use ACSR in the smaller sizes. We do not even use it in the larger sizes of over 1000 kcmil transmission conductors. We use AAC or AAAC for our lines. :smile:

 

[BlackBooker]

WOW! I would love to answer that question but I don't know what you are talking about. Electric utilities all have access to the same material but decide which materials they wish to stock and use for each situation. In addition, the linemen are very intelligent and will come up with their own ideas and submit them to the standards committees for consideration.

We use parallel cable (bare neutral with two phase conductors that are lashed together in parallel) that is clamped to the poles. The triplex service drops are attached with service grips (Chinese handcuffs - sort of) on either end. We do not attach anything that is just screwed into the poles, everything is attached to 5/8" through bolts.

You can do anything on the poles that you wish as long as it is safe and "approved". :smile:

Yea most of the time the bolts are used, but I have seen some POCO service drops attached with the screw-in type.

These chinese handcuffs you mentions is what I'm talking about. Some of the POCOs out here don't use them. Instead they take the steel strand/s in the messenger, pass thru the insulator & then wrap tightly around the messenger to effectively tie their tri-plex up. I was wondering if this is an approved method of securing cable to the insulators.

The latter half of NEC 2008 203.27 says:
"Open conductors shall be attached to fittings identified for use with service conductors or to noncombustible, non-absorbent insulators securely attached to the building or other structure."

Would this leave open the possibility of doing this to hold up the tri-plex?

 

[iwire]

The latter half of NEC 2008 203.27 says:
"Open conductors shall be attached to fittings identified for use with service conductors or to noncombustible, non-absorbent insulators securely attached to the building or other structure."

Would this leave open the possibility of doing this to hold up the tri-plex?

I am a bit confused as the NEC does not apply to anything on the utility side of the service point.

What is it exactly that your doing?

 

[BlackBooker]

I am a bit confused as the NEC does not apply to anything on the utility side of the service point.

What is it exactly that your doing?

Yeah, I know that. I don't work for a utility company, just an electrical outfit. I wanted to know if that was allowable for us to do, since we are under the NEC.

 

[mdshunk]

I think you might be confused about what you saw. The use of a "preform" might appear like they wrapped part of the bare neutral around the knob, but that's not the case.