An electrical apparatus includes a housing including an opening, an electronic component in the housing, electrical wires connected to the electronic component and extending out of the housing through the opening, a plug extending in a first direction and inserted in the opening with the electrical wires passing through the opening, and a waterproofing material in the opening. The plug includes a first outer peripheral surface matching an inner wall surface of the opening, and a second outer peripheral surface opposite and spaced apart from the inner wall surface of the opening. The electrical wires are between the second outer peripheral surface and the inner wall surface of the opening.

A control system includes a detection device and an electronic controller. The detection device is configured to detect passenger information related to at least one passenger of a human-powered vehicle driven by a driver of the human-powered vehicle in which the at least one passenger is different from the driver. The electronic controller is configured to control at least one component of the human-powered vehicle in accordance with the passenger information.

A control system includes a detection device and an electronic controller. The detection device is configured to detect passenger information related to at least one passenger of a human-powered vehicle driven by a driver of the human-powered vehicle in which the at least one passenger is different from the driver. The electronic controller is configured to control at least one component of the human-powered vehicle in accordance with the passenger information.

An electrically power assisted bicycle includes an electric motor that generates an assist force assisting human power of a rider, a detachable battery that supplies electric power to the electric motor, a headlight, and an operation panel including a display that displays information, a power button that turns on or off the electrically power assisted bicycle, an illuminance sensor that outputs a signal in accordance with received light, and a controller configured or programmed to control the headlight to be on or off. The power button and the illuminance sensor are located close to each other on or in the operation panel. After a predetermined time period passes after the controller is activated by the power button being pressed by the rider, the controller starts controlling the headlight to be on or off in accordance with the signal output by the illuminance sensor.

An electrically power assisted bicycle includes an electric motor that generates an assist force assisting human power of a rider, a detachable battery that supplies electric power to the electric motor, a headlight, and an operation panel including a display that displays information, a power button that turns on or off the electrically power assisted bicycle, an illuminance sensor that outputs a signal in accordance with received light, and a controller configured or programmed to control the headlight to be on or off. The power button and the illuminance sensor are located close to each other on or in the operation panel. After a predetermined time period passes after the controller is activated by the power button being pressed by the rider, the controller starts controlling the headlight to be on or off in accordance with the signal output by the illuminance sensor.