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View Full Version : Maximum number of spans #477 tensioned



Dbearman
02-14-2007, 03:55 PM
Could anyone tell me where to find , how to calculate or the rule of thumb on how many maximum spans of #477 ACSR that can be tensioned up at one time ?? Any info on how your company does it also appreciated.

Thanks , Bear

linemanfrog
02-14-2007, 11:17 PM
I would not think there is a max. number of spans you can sag at one time. Sag is a direct cause of tension in the wire. A properly sagged line should have the same tension for one end to the other regardless of span length or the number of spans.

Find the ruling span by using the appropriate method and then using a sag chart determine the tension you should place on the conductor to have the amount of sag that your company requires. The weight of the conductor is on the insulator or whatever you have the rollers attached to at each pole and all the deadends hold is conductor tension which is the same regardless of weather it is 10 spans or 100.

md2
02-19-2007, 07:31 PM
on a big 230kv job we sagged about 4 miles of conductor in one shot...you just have to let it sit overnight to even itself out, then jack it up again. you'll find out if you bad travellers, because the sag will seem to come up really quick