To improve the
layout of main circuit parts of an
inverter device, and the structure of the wiring between the parts, thereby accomplishing space saving for a substrate on which the circuit parts are mounted. In an
inverter device in which an electromagnetic
contactor, fuses, and input CTs are disposed between a
semiconductor module and input terminal block disposed at upper and lower end portions of a substrate, and the parts are interconnected by a
bus bar, with the electromagnetic
contactor disposed with primary side terminals and
secondary side terminals thereof facing the input terminal block and
semiconductor module respectively, and the fuses and input CTs serially connected and arranged in parallel to the sides of the electromagnetic
contactor, an R-phase and T-phase passing through the fuses and input CTs are such that the power source input terminals and the
secondary side terminals of the electromagnetic contactor are connected by
bus bars 7R-1 and 7T-1, and the primary side terminals of the electromagnetic contactor and the fuses are connected by
bus bars 7R-2 and 7T-2, thus reducing the intervals between the electromagnetic contactor and the fuses, and accomplishing a space saving for the substrate.