THERMAL PROTECTIVE DEVICE OF THREE-PHASE ELECTRICAL MACHINE

摘要

Usage: electrical, may be used to perform thermal protection of three-phase motors and other units. SUMMARY OF THE INVENTION: The device comprises a magnetic actuator with a coil, the two current transformer with primary and secondary windings, a current relay coil and the normally open contact of relay voltage to the coil and break contact, a resistor, and the primary windings of transformers configured to include a two-phase power machine, and the secondary are connected in series with one another, with a winding current relays and PTC thermistor, a current relay contact included in the coil circuit power actuator. Pozi- provided sided thermal protected analog machines, the winding voltage relay connected in parallel with thermistor and relay contact included in the coil of the actuator supply circuit in series with the current relay contact. When the machine is overloaded and the temperature reaches the critical value posistor increases its resistance and voltage drop to be supplied to the relay coil voltage, which is triggered with, opens the contact and turns off the coil actuator. 1 yl. li With