METALCLAD SWITCHGEAR DISCONNECTING DEVICE Russian patent published in 1997 - IPC

FIELD: sending signal for emergency disconnection of metalclad switchgear in case of short-circuiting electric arc across it. SUBSTANCE: device has light guide, two photoelectronic converters, current ratio log taking unit, OR circuit, analog-to-digital converter, microprocessor, and metering elements. Each end of light guide is connected to input of respective photoelectronic converter whose outputs are connected to respective inputs of OR circuit and log taking unit. Output of the latter is connected to first input of analog-to-digital converter whose second input is connected to first output of microprocessor. Output of analog-to-digital converter is connected to first input of microprocessor. OR circuit output is connected to second input of microprocessor and remaining outputs of the latter are connected to respective inputs of final elements whose number depends on number of switchgear cubicles handled by proposed device. EFFECT: enlarged functional capabilities of device which functions to disconnect separate cubicle where electric arc has appeared without disconnecting switchgear installation as a whole and to disconnect switchgear in case electric arc has appeared in two or more cubicles. 3 dwg