Provided are an electrical device and a component for an electrical device that can efficiently suppress the occurrence of a short circuit between a housing and a circuit board. The electrical device includes a housing and a circuit board housed inside the housing. The housing includes a metallic main housing to be attached to an installation section and a sub-housing attached to the main housing. The main housing includes a main wall, extending along the circuit board with a gap between the main wall and the circuit board, and a board attachment portion having the circuit board attached thereto. An insulating plate having insulating properties is fixed to an inner surface of the main wall.