How is a transformer tested with a multimeter?

Testing a transformer with a multimeter involves several steps to ensure accurate diagnostics. First, ensure the transformer is disconnected from any power source for safety. Set the multimeter to the appropriate voltage setting, usually alternating current (AC) for transformer testing. Check the primary and secondary windings by probing the terminals to measure the resistance; this should show low resistance values indicating the windings are intact. Next, test for short circuits by measuring the resistance between the windings and the core should show infinite resistance; anything else could indicate a fault. For a secondary verification, measure the AC voltage output while the transformer is powered, comparing it with its rated specifications to confirm it’s operating correctly. This method of testing helps in assessing transformer health and performance, making it a vital process in maintaining industrial oils systems and ensuring their optimal functioning.