CN2089667U

CN2089667U - Three phase ac motor protector

Info

Publication number: CN2089667U
Application number: CN 91204986
Authority: CN
Inventors: 李本青
Original assignee: SWITCH FACTORY SANMEN COUNTY ZHEJIANG PROV
Current assignee: SWITCH FACTORY SANMEN COUNTY ZHEJIANG PROV
Priority date: 1991-03-26
Filing date: 1991-03-26
Publication date: 1991-11-27

Abstract

The utility model relates to a three phase AC motor protector, which is composed of a housing, a self locking device and a phase interruption detecting device which are arranged in the housing as well as a thermal protector which is arranged in the inner of a motor. The self locking device is composed of an AC contactor, a push button and a shunt tripper, and the phase interruption detecting device is composed of a mutual inductor, a relay, a capacitor and diodes. The utility model is provided with double-protective characteristics of current mode, temperature mode, etc. and namely, the three phase AC motor protector has the protective functions of temperature, overload, locked-rotor, mechanical jamming, momentary phase interruption, empty load run, etc. Therefore, the utility model is in particular suitable for the protection of motors of submersible pump.

Description

Three phase ac motor protector

The utility model relates to three-phase AC motor protector.

The existing protector that is used for various micro-machines (three-phase star connection), its defencive function is single, as current mode motor protection starter, only plays overload protection, and temperature, the instantaneous phase failure etc. is not shielded.

The purpose of this utility model be the design a kind of multi-functional (to temperature, overload, stall, machinery block, the instantaneous phase failure) the motor protection starter.

Three-phase AC motor protector of the present utility model by housing, is installed in self-locking device, phase failure checkout gear, the line bank in the housing and the parts such as thermal protector that are installed in the motor are formed.So-called self-locking device is A.C. contactor, button and the shunt release that is connected on the three phase mains inlet wire; So-called phase failure checkout gear is the instrument transformer that connects self-locking device, connects relay, capacitor and the diode of instrument transformer.

Three-phase AC motor protector of the present utility model, its thermal protector must be installed on the asterism of motor three phase windings.

Three-phase AC motor protector of the present utility model; by the self-locking device in the housing, phase failure checkout gear and be installed in thermal protector in the motor etc. and form; existing current mode; duplicate protection characteristics such as temperature mode are arranged again, both had defencive functions such as temperature, overload, stall, machinery are blocked, the instantaneous phase failure, no-load running.Therefore, applied widely, particularly as the protection of motor for submerged pump.

Fig. 1 is the utility model motor protector scheme of installation;

Fig. 2 is the utility model motor protector line map.

Below in conjunction with accompanying drawing 1-2 embodiment of the present utility model is elaborated.

1, housing; 2, shunt release; 3, carriage; 4, relay; 5, capacitor; 6, diode; 7, electric power incoming line; 8, connect motor and thermal protector; 9, line bank; 10, instrument transformer; 11, button; 12, contactor; 13, three phase windings; 14, motor; 15, thermal protector; 16, normally-closed contact.

The utility model is a three-phase AC motor protector; this housing (1) is an iron-clad; in pressing knob down (11) close button the time; contactor (12) Bi He And mechanical lock buckles; three phase mains is connected; through cable motor (14) three phase windings (13) of flowing through, the thermal protector (15) of flowing through again arrives asterism and forms the loop electric current through the main winding of three-phase instrument transformer (10).At the same time, when electric current is flowed through instrument transformer (10) main winding, its Fu's winding just induces harmonic signal, its signal takes out after capacitor (5), flow through relay (4) and make its work of diode (6), the normally-closed contact (16) that is connected in shunt release (2) loop is opened, thereby guarantees that shunt release do not work, and impels motor normally to move by maintenance after starting.

And various faults (overload, machinery blocks, stall, the phase failure etc.) take place when motor; the capital disappears the detected triple-frequency harmonics of three-phase instrument transformer (10) immediately; the no harmonic signal of relay (4) and not working; its normally-closed contact (16) that is connected in shunt release (2) loop is closed again; make shunt release get electric work; this motor protection starter tripping operation is cut off motor power, thereby is reached the protection purpose.When temperature rise exceeded allowed band, the thermal protector (15) in the motor was worked again.

Claims

1, a kind of three-phase AC motor protector by housing, is installed in self-locking device, phase failure checkout gear, the line bank in the housing and the parts such as thermal protector that are installed in the motor are formed, and it is characterized in that:

A, self-locking device are A.C. contactor (12), button (11) and the shunt releases (2) that is connected on the three phase mains inlet wire;

B, phase failure checkout gear are the instrument transformers (10) that connects self-locking device, connect relay (4), capacitor (5) and the diode (6) of instrument transformer.

2, three-phase AC motor protector as claimed in claim 1 is characterized in that thermal protector (15) is installed on the asterism of motor (14) three phase windings (13).