When the short circuit occurs on the electric distribution system, the large current flows into the short circuit point from the induction motors as well as the generators. The formulas which calculate the short circuit current are already studied. The formulas are presented by various constants which are affected by the resistances and leakage reactances of the induction motors. In this paper, these constants are studiedd with regard to the influences of the motor speed, motor output and impedances of the feeder cables connected to the motors. The most remarkable feature is that the short circuit current becomes the maximum value at the special length of the cable. As the result of these studies on the constants in the short circuit current calculation formulas of the marine use induction motors, it becomes clear that the approximate formulas are useful in case that the length of the feeder cables connected to the induction motors is short.

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