| 摘要 |
PURPOSE:To enhance the reliability by composing a circuit for generating a light gate signal of two systems, and switching the overvoltage firing of the systems by detecting the current of a snubber circuit or the temperature of a snubber resistor. CONSTITUTION:A light gate signal generator is composed of two systems of A system of light emitting diodes 2-1A-2-NA, and B system of light emitting diodes 2-1B-2-NB. The lights of the diodes are applied to phototrigger thyristors 6-1-6-N with overvoltage protecting functions by 2-branch light guide 5. The temperatures of snubber resistors 8-1-8-N are respectively detected by temperature detectors 10-1-10-N, a switch 15 is switched by the detected output to switch the systems of the light gate signal generator. |
