In which, copper losses depends on the current through transformer primary and secondary windings as per the load. Whereas, core losses depend on applied voltage and frequency. In short, transformers are characterized only by the magnitude of the voltage and current for a designed frequency (and not by power factor which is decided by the load). read more
The power factor of transformer is not given . Because the power factor of the transformer depend on the type of load and transformer manufacturer don't know that which types of load is given to the transformer. read more
Power Factor Test Voltages. Corona can be a problem when testing dry-type transformers, so it is recommended that a power factor test be conducted at a lower voltage (something below the corona inception point) and then at the normal test voltage. If the low-voltage test result is satisfactory, then the test can proceed at the normal test voltage. read more