SPARK PROTECTION DEVICE Russian patent published in 2020 - IPC E21F9/00 H02H9/00 

FIELD: electrical equipment.

SUBSTANCE: invention relates to electrical equipment, and can be used in oil and gas, ore and flour industries, and is intended for use in explosion-proof electrical equipment, having independent power sources in form of internal voltage sources and used for operation in explosive environments. Spark protection device has a field MIS transistor connected in inverse manner: source of MIS-transistor is connected to positive terminal of device, and drain to power supply circuit of device electronics, between source and gate is connected output of optoelectronic driver, polarity of which, when the optoelectronic driver is turned on, coincides with polarity of MIS-transistor gate opening, and input of optoelectronic driver is connected through limiting resistor between positive and negative terminals of device. Spark protection device allows cascade connection to increase the number of spark protection diodes to two or three in compliance with the required level of explosion safety. MIS-transistor channels are connected in series in the supply circuit, and the input circuits of the optoelectronic drivers are connected in series and connected through a common limiting resistor.

EFFECT: reduction of voltage drop in spark-proof circuit of explosion-proof device with internal source of voltage for reduction of heat losses and increase of accuracy of control of accumulator batteries charging from external charging device.

1 cl, 2 dwg