A terminal plate includes a main portion having a screw hole, and a first and second leg portion which protrude from the main portion in the same direction. The first leg portion is formed longer than the second leg portion. The device housing includes an outer wall which has a first attachment hole into which the first leg portion is inserted, a second attachment hole into which the second leg portion is inserted, and a depressed portion into which the terminal screw is inserted. The printed wiring board is electrically connected to the first leg portion, and a center of the screw hole of is misaligned with respect to a straight line extending through a center of the first attachment hole and a center of the second attachment hole when the terminal plate is attached to the device housing and seen in a direction perpendicular to the main portion.