Preventive maintenance provides a key tool for minimizing the chances of catastrophic equipment failures. One type of preventive maintenance testing lies in testing done with equipment such as the Doble Power Factor test set. Power factor tests evaluate the quality and integrity of electrical equipment insulation.
Briefly, power factor tests compare the capacitive current to the resistive current used by a piece of equipment. If the capacitive current becomes large in relation to the resistive current, it indicates a potential problem with the insulation. Insulation breakdown often leads to equipment breakdown.
Both the Doble unit and the Megger Insulation Test sets perform tests for power factor.To test the equipment, voltage is applied to the conductors while measuring losses to ground. By comparing the results to a library of historical results, abnormal conditions can be easily identified. Further tests can help determine exactly where the problem exists.
While power factor testing usually involves transformers and breakers, tests can be useful on other types of equipment such as switches, motors and voltage regulators. As well, running these tests to generate a profile for your specific equipment allows trending analysis. Such analysis can be used to anticipate problems well before they become a major headache.