One of the maintenance actions of the equipment at the substation is temperature measurement using Thermal Imagers which is usually called the Thermovision measurement. Non-touch temperature measurements also have a disadvantage in obtaining the actual temperature of the measured object. This is due to the emissivity of an object that varies from 0 to 1. This thesis discusses the validation method to test whether the measurement is accurate and precise according to the parameters used. The results obtained are the emissivity of the substation equipment although 1 type of material, but varies emissivity due to several factors, with the accuracy of each bay transformer 1-3 is 98.41%, 98.30%, and 98.33%. While the precision of each is 1.88%, 7.98%, and 4,42%