INDICATOR OF DEGREE OF EXPLOSIVENESS OF GAS AND AIR MIXTURE Russian patent published in 1997 - IPC

FIELD: analysis of gas and air mixtures with catalytic oxidation, indication in systems of explosion-warning and test of degree of explosiveness of dangerously explosive objects. SUBSTANCE: indicator has generator of pulses of stable relative duration, device feeding transducer in the form of pulse voltage source, synchronous detector with two inputs and one output. Controlling input of synchronous detector is connected to output of generator of pulses which relative duration of output pulses is set by relationship Q = V2s

/V2p, where Q is relative duration; V_s is supply voltage of secondary devices; V_p is supply voltage of primary device (sensor). Indicator enables equivalent sensitivity of sensor to be raised V_s/V_p times which is especially effective for selective mode. In this case power supply system of sensor is connected directly to common supply voltage and power developed across sensor corresponds to rated one. Average current consumed by sensor with such connection is Q times less than pulse one and V_s/V_p times less than rated current of sensor. EFFECT: enhanced operational reliability and stability of indicator. 1 cl, 3 dwg