OMICRON GAS ALARM SYSTEM - OGS 2.1 is a micro controller based gas alarm system, built for detection of potential toxic or explosive gases in pump room or other locations. The most common gases to detect are hydrocarbon gases in LEL concentration, oxygen, and hydrogen-sulphide.
OGS 2.1 is the model name. The next figures in indicate the composition of sensors in the system. Ex. OGS 2.1 / 2-2-1 indicates 2xHC, 2xH2S and 1xO2 sensors.
OGS 2.1 consists of one cabinet including all electronics, terminals for sensor connections and the operator panel.
Any type of gas sensor can be connected to the system, provided that the sensor output is 4-20mA or 0-10V, and the sensor fulfil possible Ex-proof requirements for the intended operating area.
Sensor loops are continuously monitored for under and over current. Loop failures and other system failures are indicated on designated alarm LED’s. Each channel has adjustable alarm set points with designated alarm LED’s for each set point. Each channel has further a digital display showing the actual gas concentration.
The system is fitted with potential free change-over relay contacts for power failure, common gas alarms (one for each gas type), and for system failures.

Photos: 
Download draft: