Spark detector gas burner - filters out and amplifies HF components present when there is spark and controls gas flow to burner

摘要

To detect the presence of a spark in a spark ignition gas burner, high frequency harmonics, which are present at the electrodes only when there is an arc, are detected via a high value resistor connected to the high voltage side of the spark transformer. The resistor reduces the voltage to a level suitable for the high pass filter which removes the supply frequency, feeding only high frequency harmonics to an amplifier which passes the amplified harmonic voltages to a control box. The control box regulates the flow of gas, using for example thyristors and solenoids. The gas supply vane is closed till an arc is detected, so no gas can flow to the burner till a spark is present to ignite the gas, thus reducing the danger of explosion.