[saturnnights]

I was thinking about this recently. During the really big blackout several years ago, an overloaded line in NE Ohio had gotten so warm that it drooped down far enough to arc into a tree that had gotten a little too tall (and was too close to the line). Anyway, I know that a 120v hair dryer cord can get pretty hot so I started to wonder about transmission lines. How warm do they get when the load's really high? I'm sure that the line in NE Ohio was already warm from the sun beating down on it, but they said that the heavy air-conditioning load that afternoon had caused the lines to droop even more. So, how warm do transmission lines actually get? Too hot to touch comfortably when doing barehand work? Or just a few degrees warmer than the air around them?
Does anybody have any statistics or info on transmission line temperatures under heavy load?

Thanks,
Mark

[wood stabber]

Hot enough to get soft and bag down or come apart when there's a huge load,like 110 degree's in August in S.Cali and EVERY ONES got here ac on!

[Bipeflier]

High Temp Conductor Shoe
This will give you a ballpark look at what the "new" stuff will run.

[TLGirl]

It depends on the line loading and the ambient conditions.
In our utility, 230 kV ACSR lines are designed for 100Celcius, wheareas ACSS conductor is allowed to reach 150C. New "high temperature low sag" conductors like ACCR may reach up to 250C safely.

Under normal conditions, the conductor will generally never get that hot. But under very high loading and extreme weather conditions, it's possible.

[Lightningrod]

Welcome to the site TLGirl, You are correct on the newer conductors and thier increased heat resistance. This comes at a time utilities are looking at reconductoring and increasing capacity of existing circuits due to the troubles involved in finding new easements for exspansion of facilities.