To warn a user about the abnormality of an input voltage since, when an abnormal voltage is applied to an inverter for a concrete vibrator, a user who works in a place far away from the inverter cannot recognize the abnormality of the input voltage with the display of a voltage display meter provided to the inverter.

In the inverter for a concrete vibrator, an input voltage detector 8 provided to the inverter 1 is used to detect an input voltage allowing that whether the input voltage is appropriate or abnormal to be recognized by a display light 2 provided to the inverter, or by an intermittent pulse generated by a vibrator body 7, or by the combination of these.