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  1. #1

    Default down guy tension?

    In "The Guidebook for Lineman and Cablemen" on page 522 under calculating tension on a loaded down guy is that formula correct? For the life of me i can't get their formula to work with their numbers based on their figure 15-39 on page 523.

  2. #2
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    Quote Originally Posted by scratchpad View Post
    In "The Guidebook for Lineman and Cablemen" on page 522 under calculating tension on a loaded down guy is that formula correct? For the life of me i can't get their formula to work with their numbers based on their figure 15-39 on page 523.
    Is it possible to give the formula & numbers for those who do not have the book?

  3. #3
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    don't recall ever using the formula.......seems like we pulled em until we got the pole where we needed or wanted it.....

    on many single phase DE and angles, we raked the pole back, made the down guy up and then after we got the wire pulled in, if we needed more, we just took some more up on the downguy.........

    We might have been cheating a little
    Old Lineman Never Die......We Just Don't Raise Our Booms As Often

  4. #4

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    Quote Originally Posted by Trbl639 View Post
    don't recall ever using the formula.......seems like we pulled em until we got the pole where we needed or wanted it.....

    on many single phase DE and angles, we raked the pole back, made the down guy up and then after we got the wire pulled in, if we needed more, we just took some more up on the downguy.........

    We might have been cheating a little
    exactly, and we could have 3 dead ends done before they get the formula figured out

  5. #5

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    Quote Originally Posted by lewy View Post
    Is it possible to give the formula & numbers for those who do not have the book?
    Guy Tension = T X square root of L sq. + H sq. / L

    H= height of guy attachment
    L= length of guy lead
    T= tension of the conductors held by the down guy

    Their figure has the guy attachment 50ft. from ground level, guy length at 58ft., guy lead at 30 ft. and conductor tension at 1,000lbs.

    so their answer to their figure is

    Guy Tension = 1,000 X square root of 30 sq. + 50 sq. / 30 = 1,944lbs.

  6. Default

    Quote Originally Posted by scratchpad View Post
    Guy Tension = T X square root of L sq. + H sq. / L

    H= height of guy attachment
    L= length of guy lead
    T= tension of the conductors held by the down guy

    Their figure has the guy attachment 50ft. from ground level, guy length at 58ft., guy lead at 30 ft. and conductor tension at 1,000lbs.

    so their answer to their figure is

    Guy Tension = 1,000 X square root of 30 sq. + 50 sq. / 30 = 1,944lbs.
    I don't think my brain could take the calculations but heres what linemen need to see. I think!
    Change the lead from 30 ft. to 20 ft. and re-calculate.
    Why I say this is that often there isn't enough easement for a proper lead and I believe that is the reason the proper sag gets lost.
    The Old Lineman

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    Quote Originally Posted by kooman View Post
    exactly, and we could have 3 dead ends done before they get the formula figured out
    Quote Originally Posted by old lineman View Post
    I don't think my brain could take the calculations but heres what linemen need to see. I think!
    Change the lead from 30 ft. to 20 ft. and re-calculate.
    Why I say this is that often there isn't enough easement for a proper lead and I believe that is the reason the proper sag gets lost.
    The Old Lineman
    Right on both counts!!
    Old Lineman Never Die......We Just Don't Raise Our Booms As Often

  8. #8
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    Quote Originally Posted by Trbl639 View Post
    Right on both counts!!


    Is that the reason I see a lot of bow and arrow poles when driving through the country?

  9. #9

    Default Guy tension formula

    Well the formula works. Our easy rule of thumb was raking the pole 1 1/2 per five feet of pole. Ie: 50 ft pole gets 7.5 inches of rake. When the wire is larger consider a pole top width.

  10. #10
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    Feb 2007
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    Quote Originally Posted by old lineman View Post
    I don't think my brain could take the calculations but heres what linemen need to see. I think!
    Change the lead from 30 ft. to 20 ft. and re-calculate.
    Why I say this is that often there isn't enough easement for a proper lead and I believe that is the reason the proper sag gets lost.
    The Old Lineman

    That is why you would have your dead end pole done properly and use a slack span to get to your next easement take off. A slack span looks better than a D.E. pole that is leaning into the tension or bowed out of shape.

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