FIELD: surge voltage protective gear.
SUBSTANCE: proposed device has differential circuit breaker (cutoff unit), phase circuit incorporating fixed phase contact, movable phase contact, neutral circuit provided with fixed neutral contact and movable neutral contact, mechanism for hand operation by means of control lever and for automatic operation by means of off-operating gear, differential transformer with toroidal magnetic core carrying primary phase winding and secondary measuring winding coupled with off-operation relay operating in conjunction with off-operation gear, with check circuit incorporating reference resistor, and with push-button; novelty is that device is provided with newly introduced dynistor, potentiometer, super-beta transistor, diode bridge, and four resistors; input leads of diode bridge are connected, respectively, to input neutral lead of differential circuit breaker and to output phase lead of the latter; dynistor is inserted between center tap of first resistor circuit and potentiometer whose central lead is connected to center tap of same first resistor circuit and potentiometer, as well as to output of divider built around second and third resistors, with its center tap connected to base of super-beta transistor whose emitter is connected to third single lead of potentiometer, lead of third resistor, and first output of diode bridge, and its collector is connected through fourth resistor to second lead of first resistor and to second output of diode bridge.
EFFECT: enlarged range and enhanced precision of setting maximal disconnecting voltage; enhanced economic efficiency and operating stability of device.
1 cl, 1 dwg
