Sag tension/temperature test

Sag is the vertical distance between the anchor point and lowest point of the conductor. This test is usually carried out on overhead conductors, as excessive sagging can have severe consequences on overhead systems, including violation of electrical clearance distances, line breakage, tower or pole damage or even collapse. This test will determine the sag of the conductor at a given span at various temperatures. It will confirm if preliminary sag calculations are correct and provide proof of reliability of a given conductor. A similar set-up can be used to simulate ice-loading.

This test can be carried out on stranded conductor and overhead catenary systems. Lamifil’s internal method is based on the CIGRE 426 § 4.12 standard.

  • Lamifil has a unique indoor sag temperature testing facility allowing span lengths of 108 m.
  • Currents of up to 4000A and up to 10 tons of force can be handled.
  • All sag temperature tests are fully accredited.
  • Lamifil has unique in-house expertise to interpret results.
  • Our lab has experience with all conductor types (HTLS, GAP,…).
  • A realistic simulation is set up by mounting a conductor between two dead-ends. The dead-ends are fixed between two towers with a span length of 108 m;
  • Current is applied to the conductor (up to 4000A), causing the conductor to heat and sag;
  • Both temperature and the resulting sag are measured throughout time, respectively by a data logger and a string potentiometer;
  • Measurements are plotted in a sag/temperature curve and are subsequently compared to sag calculations;
  • A full report is prepared including test object data, test description, set-up, procedure results and conclusions.

How can we help?

Lamifil nv

Member of Koramic Investments

Frederic Sheidlaan
B-2620 Hemiksem
Belgium

t + 32 (0)3 8700 611
f + 32 (0)3 8878 059