A cover includes a cover body and an interlock connector. The cover body covers an opening provided in a case of a power conversion device and is electrically conductive. The interlock connector is electrically connectable to a receptacle connector provided inside the case. A noise shielding layer and a low conductivity layer are formed between the cover body and the interlock connector. The noise shielding layer is electrically conductive. The low conductivity layer is closer to the cover body than the noise shielding layer is, and is less electrically conductive than the cover body and the noise shielding layer.