Priority switches are used in installations where the existing conductor cross-sections or the size of the power supply connection do not allow two high-power consumers to operate simultaneously (e.g. storage heater and heat exchanger). Priority switches disconnect the long-term consumer (storage heater) as long as the short-term consumer (heat exchanger) is switched on. The current coil of the priority switch is connected in series with the short-term consumer. When the consumer is switched on, the breaker of the priority switch disconnects the contactor of the heating system, for example.