Abstract: A connector apparatus capable of connecting with a complimentary connector for the supply of energy, signals or a commodity has a connector part which can be retracted into the apparatus in response to a control signal to disengage the complimentary connector. The retraction movement may be caused by a piston and cylinder arrangement or by an electromagnet. The connector arrangement has many applications and may be released in response to a variety of circumstances. For example, it may be used in a power supply to a garaged vehicle or grounded aircraft and be arranged to release upon release of the vehicle or aircraft brakes. It may be used in a discharge or filling hose from or to a tanker vehicle and be arranged to release upon starting of the vehicle. It may furthermore be connected in a gas or water supply and be arranged to release in response to a signal from a gas or moisture detector.