Independent detector by catalytic technology for the detection of explosive gases with relay. Independent functioning: does not require central. Allows the automatic selection of the gas to detect , between any of the available gases, through a protocol established with a jumper. Detection range from 0 to 100% L.I.E. Opticas state and sensor breakout indicator. 1 alarm relay output programmable between 2 levels (20% LIE / 50% LIE), instant/retarded disconnection, programmation retard of connection and initial state of the relay in repose. Power 10V to 30V DC. Sensor and compensator in independent encapsulation to provide a bigger linearity and stability. Detector with sintered filter. Calibrated in factory withspan gas. No need to recalibrate in the installation. Easy verification and maintenance operations by a single worker.