The rugged Megger PA-2505K Phantom Load operates from a single-phase source and is designed for field-testing single-phase and polyphase watthour meters at 50 and 100% power factor. The Megger PA-2505K utilizes a heavy-duty selector switch in conjunction with a variable autotransformer to provide continuous adjustment of the load current. This is a valuable feature that permits close control of the output for different load circuit impedances or in the event of variations in the source voltage.
The Megger PA-2505K unit is rated for continuous duty with forced-air cooling provided by a built-in fan. Primary and secondary test leads are furnished as standard equipment. This phantom load provides a controlled source of current for testing watthour meters. The test current and the rated operating voltage of the meter are simultaneously applied to the meter under test and to a calibrated watthour meter, commonly called a watthour standard. To determine the accuracy of the meter under test, its operation is compared to that of the watthour standard.