lightpole heights

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Cavie

Cavie

Senior Member
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SW Florida
I think I remember someone here posting a method of estimating the hight of a light pole by eyesite. I need to figure the hight of POCO Transmission lines (230,000 volts) over a proposed traffic signal intersection. I am getting the runaround from the Poco and need just a quick estimate of the hight of the lines. I know I will get the correct answer for the Poco Transmission Division someday but need to do some quick math to see if the proposed 46' poles will fit under with 13' clearance.
 
Use a standard carpenters' square.

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Walk away from the pole until you can sight the top along the 45? angle side of the square while the bottom is level. Now measure your distance from the pole. That's the pole height.
 
480sparky said:
Use a standard carpenters' square.

418B728T71L._SL500_AA280_.jpg




Walk away from the pole until you can sight the top along the 45? angle side of the square while the bottom is level. Now measure your distance from the pole. That's the pole height.
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I agree (or any similar triangulation method). I usually use an inclinometer, which is basically the same thing. Also use a laser gun and a measuring pole.

While the birthmark is ok in general (SOP is 10% + 2.5 ft), it is not accurate enough for most clearance issues. Add: and won't help you in mid-span.
 
480sparky said:
Use a standard carpenters' square.

418B728T71L._SL500_AA280_.jpg




Walk away from the pole until you can sight the top along the 45? angle side of the square while the bottom is level. Now measure your distance from the pole. That's the pole height.
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It is if your eyeball is on the ground :). Add the distance from the ground to your eye to get the correct answer. Of course this is all assuming the ground is level.
 
Cavie said:
...hight of a light pole...hight of the lines
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I might mention that along with this quick math you need to account for the maximum sag on those conductors. There may be several feet of sag that you have to account for that may not be present when you measure.
 
a transit that is level and at a tilt up at 45 degrees would allow you to see the lines. I would demand a certified letter from poco engineer as to his readings and then try one of the suggested methods to confirm. To set the poles you will need enough distance for crane and entire pole length. I dont think as an inspector you should be required to do this measurement.
 
Jim W in Tampa said:
...I dont think as an inspector you should be required to do this measurement.
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He can't be. I think he just wants a rough estimate. The POCO is going to have to give the final answer as they are the only ones with the required data.
 
mivey said:
He can't be. I think he just wants a rough estimate. The POCO is going to have to give the final answer as they are the only ones with the required data.
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That is correct. I do not wish to do this intersection at all. Neither does my Level 3 technician. The signal span has been designed by a non electric engineer and it runs parallel to the overhead transmission lines. The POCO has not signed off on this design which is on it's 3rd revision. I just looking for something to give my superiors to make it go away. I have already told then that I will not attach my EC license to this project but it is falling on def ears. I do know that a 4' sag is not uncommon in the summertime.
 
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Cavie said:
That is correct. I do not wish to do this intersection at all. Neither does my Level 3 technician. The signal span has been designed by a non electric engineer and it runs parallel to the overhead transmission lines. The POCO has not signed off on this design which is on it's 3rd revision. I just looking for something to give my superiors to make it go away. I have already told then that I will not attach my EC license to this project but it is falling on def ears. I do know that a 4' sag is not uncommon in the summertime.
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There are times you must simply use the NO word. I would never do something i feel is unsafe just to make others rich. Do they not understand induction ? You have 1/2 of a turn and at that voltage could be a serious problem not only for the workers but for electronics. If it was me i think i would walk away
 
Jim W in Tampa said:
There are times you must simply use the NO word. I would never do something i feel is unsafe just to make others rich. Do they not understand induction ? You have 1/2 of a turn and at that voltage could be a serious problem not only for the workers but for electronics. If it was me i think i would walk away
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Traffic cameras do not work there. The county signal techs have story's of hire standing up on there arms and arching. No my superiors do not understand induction. They know dirt and blacktop.
 
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