An apparatus includes an enclosure, a power switch, one or more power converters and a wire. The enclosure may include a door and one or more apertures. The enclosure may be mechanically attachable to an external side of an industrial control panel with the apertures aligned to one or more openings in a wall of the industrial control panel. The power switch may be mounted inside the enclosure and configured to switch electrical power from a line-side power line to a load-side power line. The load-side power line may be configured to transfer the electrical power through at least one of the apertures. The power converters may be configured to generate a low-voltage electrical power from the electrical power. The wire may be configured to transfer the low-voltage electrical power through at least one of the apertures.