Induction

[mrdave]

I am running Al. URD cable to a temp pole.(120/240 single phase)
I need to have @50ft of extra wire at pole so it can be extended to house when built.
I was planning on coiling it up in plastic ground vault with an additional 50 feet of wire coiled up going from temp pole out to another feeder panel at pump house. Same type wire.

Do I need to worry about any problems with induction from the coils?
I don't want any problems with well pumps! $$$

Anyone have a clue?

 

[mdshunk]

Coil it in a figure 8

 

[ItsHot]

Leno

Leno

Coil it in a figure 8

Keep it going Marc, and I want have to watch Leno tonight!

 

[mdshunk]

Keep it going Marc, and I want have to watch Leno tonight!

I think that the figure 8 slack coil stowage method is an old wive's tale to cancel inductive forces. I just wanted to throw that out there so someone could jump on that and take it from there, but you forced my hand early. I can't honestly say if coiling in a figure 8 has any benefit or not. I know that when they leave slack loops in buried primary, they do so in a figure 8 pattern. That was pretty old-school, however. Not so many slack loops being installed nowadays.

 

[cadpoint]

Set the pole, I won't run service till required! But, if you really feel the need, run and stop on pole in the air and use the new aerial quick connects. Maybe ones just creating a splice but they are capped by design, and then ready for the next run required !

I'd run underground, and I understand the possible reasons why one couldn't.

I'm still suffer from a serve lateral pole that had to placed on my property, why, cause people keep knocking the main poles down. The POCO is try'n to hide the service poles behind the trees and spreading them out.

I won't lay AL on the ground much less in the air the way things are!
Edit to add:
Lineman are having a trouble time with thief also.

 

[mrdave]

Coiling

Coiling

Can't run above ground here. I need to put in temp pole now as meter is @ 200 feet from construction site and another 200 feet to pump house. (6 acres, not city lot.) I don't want to do any splices, that's why I want to coil wire.

Is there any validity to the Figure 8 coiling. That's what I was thinking In the first place. I was hoping to get a more informed input than my educated guess.

Thanks.

 

[don_resqcapt19]

The biggest reason to coil anything in a figure 8 is to avoid twists and kinks when coiling and uncoiling.

 

[K8MHZ]

I see the POCO coil wire in round loops here all the time.

I don't see where there could be an issue of induction if there is no current flowing through the conductor, and if there is, the neutral running with the ungrounded conductor should counteract any inductive issues.

 

[zbang]

I keep wondering why this old bit keeps popping up. The only induction problem with round coils is when you're doing single conductors or have some really nice leakage currents to unbalance the flows. (And, the only thing that figure-8s help with the twist*. They'll still 'induct' with single conductors since the turns in each lobe run the same way.)

*I'm a big fan of the flip-coil, where every other turn is kind of tucked under itself. It serves the same purpose as a figure-8, but takes less space. It's really handy for that 100' piece of 4/4 SOW .

 

[RHJohnson]

The figure 8 was for the reason stated earlier - easier to uncoil the loops.
We have made 100's of installations where we required 200'-250' slack coiled up. Did each of these in 1 large coil, the slack being taken off 1 coil at a time over about 2 years before the job was finished. (This was 3ph480vac)
Was never a problem....