The EGS is a gas warning device, especially optimized for detecting refrigerant leaks in cooling plants. If the sensor element detects one of the refrigerants (CFC's) listed below, then 2 relays will switch, each at a specific threshold value. The relay states will be indicated by LED's, the relay position can be preset (depending on type) by jumpers. With relay 1 e.g. a ventilation system can be switched on, Relay 2 can be used to shut down the plant or to forward an alarm message. After the gas concentration has dropped down, the relays will reset. The correct function of the sensor element is monitored internally, LED 'Sensor-Malfunction' (not 2101) indicates if the sensor does not work correctly. A special function allows to adapt the EGS to environments where a few gas permanently exists (e.g. rooms which must be cleaned by detergents daily) to prevent faulty alarms. The EGS (not 101) can be networked via an RS-485- interface, parameters can be set and read out by PC-software