738-1993 IEEE STANDARD FOR CALCULATING THE CURRENT-TEMPERATURE RELATIONSHIP OF BARE OVERHEAD CONDUCTORS

Losses in the transmission lines most especially in the overhead bare type of conductors does not only depends on the load it carries or the resistance it possesses. Although these are the major factors to consider, we can not deny the fact that the temperature also contributes a lot. Resistance of any metallic object tends to increase as temperature rises. As a result, we can say that line losses in transmission lines are directly proportional to the temperature.

IEEE Standard 738-1993 is a simplified method of calculating the current-temperature relationship of bare overhead lines, given the weather conditions, is presented. Along with a mathematical method, sources of the values to be used in the calculation are indicated. This standard does not undertake to list actual temperature-capacity relationships for a large number of conductors for a large number of conditions.

The purpose of this standard is to present a method of calculating the current-temperature relationship of
bare overhead conductors.
Conductor surface temperatures are a function of
a) Conductor material properties
b) Conductor diameter
c) Conductor surface conditions
d) Ambient weather conditions
e) Conductor electrical current

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