sag is the difference between the point of support to the lowest point of the conductor.
The plural of sag is sags, not sag's! Sag is caused by the weight of the conductor between its supports, and is (a) unavoidable and (b) necessary to allow for the conductor's expansion and contraction during variations in temperature. When surveyors design a power line, the amount of necessary sag is calculated and built into the design, while ensuring that the clearance between the conductor and the ground remains within safe limits.
sag
SAG
Doosan Power Systems's population is 6,000.
Ballard Power Systems's population is 699.
Vericor Power Systems was created in 2000.
Generac Power Systems was created in 1959.
The population of Generac Power Systems is 1,500.
Offshore Power Systems was created in 1970.
Offshore Power Systems ended in 1984.
Ballard Power Systems was created in 1979.
The sag setting is necessary because it is physically impossible to have a suspended line with no sag. The sag is specified because there has to be a minimum clearance value for the height above ground at the centre of the sag where the cable is at its minimum height.