Why do they tramp transmission lines?

[z27916]

I've asked this question a few times when driving by tramp towers but I've got a couple different answers and nobody I have talked to seems confident as to why that is done.
Can anybody explain this to me or refer me to a source that gets into the theory behind it a little.
Thanks for your time

Zac

[US & CA Tramp]

The simplest explanation is it reduces electromagnetic coupling which controls the operating frequency within normal limits.

You might try to google it to find more information.

[bluestreak]

Never heard the term tramp tower before and I worked transmission for the better part of 18 year maybe a regional thing, I googled it and all I got was an auto correct for Trump towers in New York and a drag queen in Ohio. Can you explain of maybe a picture.

[Orgnizdlbr]

Never heard the term tramp tower before and I worked transmission for the better part of 18 year maybe a regional thing, I googled it and all I got was an auto correct for Trump towers in New York and a drag queen in Ohio. Can you explain of maybe a picture.


Same here.......

[Lineman North Florida]

Same here.......

Here as well.

[Pootnaigle]

Me neither

[Rob]

Same here....

[bren guzzi]

Over in the uk... I've worked transmission. Never heard of it either. " explain please " :confused:

[loodvig]

The only 'tramp' I ever heard of is a man who travels all over working different jobs.

[splinter]

I think he's talking about trampositions.

[Pootnaigle]

Um is that the same as a transposition?

[bren guzzi]

I think he's talking about trampositions.

I think that's that's the hobo karma sutra ..:confused:

[barehander]

You guys are killing me again.....
As most of you know, when you work on a line in proximity of Transmission, there is an induced voltage on that line. It works the same way on a transmission line. On any configuration, horizontal or verticle, there is induced voltages. The center phase has both other phases inducing voltage on it, where the outside phase only have 1, the center phase. For that reason, the center phase reacts with overvoltage. It affects the relays at subs, so what they do is roll it every so often which equallizes all that induction.....

[T-Man]

You guys are killing me again.....
As most of you know, when you work on a line in proximity of Transmission, there is an induced voltage on that line. It works the same way on a transmission line. On any configuration, horizontal or verticle, there is induced voltages. The center phase has both other phases inducing voltage on it, where the outside phase only have 1, the center phase. For that reason, the center phase reacts with overvoltage. It affects the relays at subs, so what they do is roll it every so often which equallizes all that induction.....

Great explanation BH, We used to do that on our sub-transmission back in the seventies, then they stopped and straightened all those transitions out. Haven't noticed them on the transmission lines, but I guess I wasn't looking for them either. The reason they did that was just as you said. . .to prevent induction on one phase more than the others.

[bluestreak]

Best as I can recall never ran into a situation where the conductor was purposely rolled for that reason, the only time I've seen a line rolled was to get a phase match at a tie point. Back in the eighties we did a project that was called Fire Protection, there was a problem where you had two or more 345 kv lines on the ROW and on corners the the outside pole on the inside line "Hows that for confusing I should be a politician" Were burning off at the conductor band, evidently the induction from the two lines would concentrate on that pole at the band and start the pole on fire it looked like a pole that burns off at the neutral when the primary ins was leaking. The fix was to run three or four additional ground wires ten to fifteen feet above and below the conductor band and make sure everything was bonded and we would also put a creosote pole topper on the top of the pole to keep the moisture out of the heart of the pole.

[barehander]

Tramps are everywhere, here's a few on 500kv, 115kv, and then a 70kv line rolled between 2 poles with offset side posts.

6101610261036104

[Lineman North Florida]

Tramps are everywhere, here's a few on 500kv, 115kv, and then a 70kv line rolled between 2 poles with offset side posts.

6101610261036104 I've never seen anything that resembles that here in the Southeast, not saying it doesn't exist, just saying I have never seen it down here.

[Rob]

I've never seen anything that resembles that here in the Southeast, not saying it doesn't exist, just saying I have never seen it down here.

Haven't seen that in the Northeast either.

[tramp67]

Like Barehander said, they put the transpositions, or tramps, in the transmission lines every so often to counteract the effects of induction between the phases. I've seen them all over the country, from National Grid in the Northeast to ComEd in the Midwest to BPA on the West Coast. Its actually becoming a more common practice on longer transmission lines because it also helps reduce induction onto adjacent circuits as well as affecting fault detection and relaying sensitivity. Some of the tramp structures are very interesting to look at:)

[z27916]

Thanks barehander.