INTRINSICALLY SAFE EXPLOSION−PROOF SENSOR CIRCUIT

摘要

An intrinsically safe explosion−proof sensor circuit is realized through a simple system. An intrinsically safe explosion−proof sensor signal processing circuit is characterized by comprising a sensor section for measuring a physical quantity of an object disposed in a dangerous place and a safety keeping circuit disposed in an explosion−proof case in a no dangerous or a dangerous place and provided with driving and feedback operational amplifier circuits and a current limiting resistor connected in series with each signal line connected with the sensor section and with the output terminal and the negative input terminal of the corresponding operational amplifier. Alternatively, the explosion−proof sensor signal processing circuit is characterized in that blocking capacitors are employed in place of the current limiting resistor.