To provide a system which can connect a general load which operates on a single-phase AC with an inductive load which operates on a three-phase AC.

The general load, which operates on the single-phase AC power, and the inductive load, which operates on the three-phase AC power, are connected as one system with an emergency power source consisting of a solar cell and a storage battery which has accumulated the power generated by the solar cell. It has an inverter which converts the output of the emergency power source into a single-phase AC power, being connected with the emergency power source, and a variable-voltage variable-frequency inverter which is connected with the output end of the inverter. The general load operates on the supplied single-phase AC power, being connected with the inverter, and the inductive load operates on the output from the inverter via the variable-voltage variable-frequency inverter.