The Gasmaster GM-4 gas detector is a reliable, stationary warning device for gases. To connect a gas sensor, the gas measuring device is optionally supplied with one to four 4 - 20 mA or mV signal inputs. Each signal input has two alarm relays with which the gas detector can control signal lamps/horns or fans, for example. Two additional relays for alarm 1 and 2 are installed inside the device. The Gasmaster gas warning system also has a third relay inside for the fault alarm. A large display shows the measured values in ppb, ppm or %. In addition, the gas detector can be equipped with an optional interface for PC configuration or for uploading the event log.