To attain downsizing and cost reduction of/in a voltage type inverter by monitoring the temperature rise in the inside and the resistor of the voltage type inverter using a temperature sensor near which the resistor is disposed.

A resistor 12a is fixed on a converter 11, the converter 11 and an inverter are fixed on a cooling fin 27, and the cooling fin 27 and the cooling fin 27 and a electrolytic capacitor 13 are fixed on a mounting leg 28. Printed circuit boards 21 to 23 are arranged on the converter 11 and the inverter. The resistor 12a, the printed circuit boards 21, 22, and the converter 11 cover the periphery with the cooling fin 27, the mounting leg 28, and a top cover 29. The temperature sensor 24 detects a temperature rise resulting from the resistor 12a being energized for a long time, and a temperature rise in the inside of a volt type inverter are detected by a temperature sensor 24. It is thus possible to contribute to downsizing and cost reduction of/in the voltage type inverter.