PROTECTION DEVICE AGAINST LOAD REVERSE POLARITY Russian patent published in 2023 - IPC H02H3/18 

FIELD: electrical engineering.

SUBSTANCE: invention relates to devices for supplying power to portable devices, for example, thermal imaging devices, which have load protection against polarity reversal. The device contains first and second relay devices (RD 1 and RD 2), each of which has two normally open contacts and control circuits, as well as first and second diodes. The anode of the first diode is connected to the cathode of the second diode, and the cathode of the first diode and the anode of the second diode are connected to the inputs of the control circuits RD 1 and RD 2, respectively. The first NO contact of RD 1 is connected between the first power bus and the positive load bus. The second closing contact of RD 1 is connected between the second power bus and the negative load bus. The first closing contact of RD 2 is connected between the first power bus and the negative load bus. The second closing contact of RD 2 is connected between the second power bus and the positive load bus. The outputs of the control circuits RD 1 and RD 2 are connected to the second power bus. A current stabilizer is additionally introduced into the device, the input of which is connected to the first power bus, and the output is connected to the anode and cathode of the first and second diodes, respectively. The closing contacts and control circuits RD 1 and RD 2 are made in the form of two normally open optoelectronic alternating current relays. The control circuit of RD 1 consists of sequentially connected LEDs of the first and second opto-relay. The LED anode of the first opto-relay is the input of the RD 1 control circuit. The LED cathode of the second opto-relay is the output of the control circuit of RD 1. The control circuit of RD 2 consists of sequentially connected LEDs of the third and fourth opto-relay. The LED cathode of the third opto-relay is the input of the RD 2 control circuit. The LED anode of the fourth opto-relay is the output of the control circuit RD 2.

EFFECT: ensuring the supply of a wide range of supply voltages in the required polarity with minimal losses of power and supply voltage for any combination of input bus connections.

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