Abstract: A system for monitoring the sag of a transmission power line. A tension measuring device is provided to the power line and a distant signal processing unit connects to the measuring device by a cable. A cable shielding arrangement is provided to protect the system from electrical transients.

Abstract: A system for determining the sag of an overhead power transmission line to prevent flashover to adjacent objects on earth. A small replica of the transmission line conductor is provided and located in proximity to the transmission line. The temperature of the replica is measured along with the ambient temperature. By appropriate calculations, the ampacity determination is made to determine the maximum permitted current through the transmission line under the particular weather conditions.

Abstract: A system for determining the sag of an overhead power transmission line to prevent flashover to adjacent objects on earth. Power line tension is measured as well as ambient temperature at two different times. From these measurements the Ruling Span of a power line can be calculated from which a determination can be made of the maximum safe current to avoid unsafe line sag.

Abstract: A system for determining the sag of an overhead power transmission line to prevent flashover to adjacent objects on earth. A tension measuring device is provided to produce a sign as a function of powerline tension. The signal is processed and transmitted to a distant location by cellular communication to a distant central monitoring station. Knowing the sag-tension relationship of the monitored line the sag is determined. Thus action may be taken if the powerline sag becomes excessive.