PROTECTION DEVICE OF ELECTRIC APPLIANCES AGAINST INCREASED AND DECREASED VOLTAGE IN AC MAINS AND IMPACT OF PHASE VOLTAGE ON ZERO CONDUCTOR Russian patent published in 2013 - IPC H02H3/00 

FIELD: electricity.

SUBSTANCE: device includes input pins L, N, Nt, output pins RH, step-down transformer (1), the primary winding of which is connected at one end to phase conductor L, and its other end is grounded; secondary winding of transformer (1) is connected to rectifier bridge (2) feeding an actuation component. Mains voltage control component includes solenoid SL1 (3), inside the winding of which there is core (4) with spring (5). On one side, core (4) has adjustment screw (6), and on the other side, elongated end of core (4) has slot (7). One end of winding of solenoid (3) is connected to phase conductor L, and the other end is connected to zero conductor N. Actuation component includes LED (11) and photo diode (12), which form an optoelectronic couple through slot (7) of core (4). LED (11) is connected to rectifier bridge (2), and photo diode (12) is connected to amplifier of signal loaded to switching device K1. At optic communication between LED (11) and photo diode (12) the switching device K1 is deenergised, and electric current is supplied through normally closed contacts K 1.1 to load. At failure of optic communication, at increase or decrease of the mains voltage, the switching device K1 trips the load from electric mains through contacts K 1.1. The indication component includes two-colour light-emitting diode (15) connected through limit resistor 16 to zero conductor N, and through diodes 17 to contacts K1.1 of switching device K1.

EFFECT: improving operating reliability and simplifying electric circuit of the device.

2 cl, 1 dwg