Abstract :
TEN years´ experience with a high-power laboratory, giving approximately 1,100,000 three-phase initial symmetrical kilovolt-amperes on short circuit at the machine bus,1 has defined its usefulness and limitations and has resulted in an addition to its installed equipment. By taking advantage of assymmetry this capacity has been sufficient to demonstrate ratings up to 1,500,000 kva, and the increased testing capacity is required to demonstrate interrupting ratings of 2,500,000 kva.