CN2049442U - Solid contactor for three phase power - Google Patents

Abstract

The conventional three-phase power electromagnetic contactor has big noise, slow switching speed and short service life due to with contacts. The utility model relates to a three-phase power solid contactor, which has no contact but has the functions of overvoltage, over current and open phase protection. The utility model has the advantages of no noise, high speed, high reliability and long service, which particularly suits to be used in the quick frequency start occasion, inflammable occasion, explosive occasion, etc.

Description

Solid contactor for three phase power

The utility model belongs to the technological improvement of A.C. contactor.

Three-phase power electromagnetic contactor in the past, because the contact is arranged, noise is big during work, and switching speed is slow, does not particularly have overvoltage, and overcurrent and short-circuit protection function have reduced the reliability of contactor.

The purpose of this utility model provides a kind of contactlessly, has overvoltage, the alternating current solid-state contactor of overcurrent and short-circuit protection function.

The utility model is by casing, radiator, radiator cover with by being serially connected in respectively on A, B, the C phase line, and structurally identical bidirectional thyristor BCR ₁, capacitance-resistance absorption circuit, overvoltage protection loop, trigger the main loop circuit that the loop constitutes, and by the overload detection coil J that is serially connected in respectively on A, B, the C phase line ₁, J ₂, J ₃, transformer B ₁, full-bridge rectifier D ₁, capacitor C ₄, coil J ₄, J ₅, resistance R ₇, controllable silicon CR, vacuum switch j; External manual control is opened, is stopped button QA, TA and constitutes control loop composition, overload detection coil J ₁, J ₂, J ₃Three normally opened contact parallel connections after as the triggering loop of controllable silicon CR, as long as an overload is arranged, can make controllable silicon CR conducting, coil J ₅Must be electric, cut off the power supply of vacuum switch j, major loop is disconnected, reach the overcurrent protection purpose, the 380V alternating current is after transformation, rectification, filtering, and j provides power supply for vacuum switch.

The utlity model has following advantage: 1. contactless, noiselessness, reliability height, the life-span is long, volume is little, in light weight; 2. occasions such as switching speed is fast, has overvoltage, overcurrent and short-circuit protection function, is particularly suitable for fast frequency and starts, and is inflammable are used.

Fig. 1 is a front view of the present utility model, and Fig. 2 is that its bottom view Fig. 3 that has part section is a circuit diagram of the present utility model.

Now the utility model is described in further detail in conjunction with the accompanying drawings, and circuit structure diagram shown in Figure 1 is made up of main loop circuit and control loop circuit, and main loop circuit is by the bidirectional thyristor BCR that is serially connected in respectively on A, B, the C phase line ₁, resistance capaciting absorpting circuit, overvoltage crowbar and circuits for triggering constitute.Resistance capaciting absorpting circuit on the A phase line is by R ₁, C ₁Series connection constitutes, this circuit and piezo-resistance RV ₁Back cross-over connection in parallel is in bidirectional thyristor BCR ₁Anode and negative electrode two ends constitute overvoltage crowbar.Circuits for triggering are by current-limiting resistance R ₂Normally opened contact j with vacuum switch j ₁Series connection back cross-over connection is in BCR ₁Anode and trigger electrode two ends constitute, circuit structure on B phase line, the C phase line and the identical wherein j of circuit structure on the A phase line ₁, j ₂, j ₃By same coil j excitation,, can on A, B, C phase line, be provided with respectively by resistance R for inductive load ₈, capacitor C ₅, resistance R ₉, capacitor C C ₆, resistance R ₁₀, capacitor C ₇The capacitance-resistance absorption circuit that constitutes, and be connected into Y shape, in order to absorb the wave variation that inductive load causes.

Control section is by the overload detection magnet exciting coil J that is serially connected in respectively on A, B, the C phase line ₁, J ₂, J ₃Variator B ₁, full-bridge rectifier D ₁, capacitor C ₄, external manual control opens, stops button QA and TA, coil J ₄, J ₅, resistance R ₇, controllable silicon CR, vacuum switch j forms, coil J ₄Self holding contact J is provided ₄, overload detection magnet exciting coil J ₁, J ₂, J ₃Three normally opened contact J1,,, J ₂J ₃Back in parallel one end is connected with resistance 7, and the other end is connected with the control end of controllable silicon CR, and as the circuits for triggering of controllable silicon CR, the 380V alternating current is through transformer B ₁Transformation, full-bridge rectifier D ₁Rectification and capacitor C ₄After the filtering, j provides power supply for vacuum switch, in use, in case A, B, any one line overload of C phase line, the overload detection magnet exciting coil J on its phase line occur ₁(or J ₂, J ₃), will make its normally opened contact JJ ₁(or J ₂, J ₃) closure, thereby trigger controllable silicon CR conducting, J ₅Must be electric, make its normally-closed contact J ₅Disconnect, cut off the power supply of vacuum switch j, motor is stopped, reaching the safe operation purpose.

Main loop circuit and control loop circuit all are arranged on the circuit board 4, circuit board 4 is placed on the bottom of casing 1, and seal admittedly with epoxy resin, radiator 3 is fixed on the casing 1 by touching nail, on radiator, the radiator cover 2 that setting is made by transparent plastic, radiator cover 2 by screw on casing 1.

During use; three-phase power line is received respectively on A, B, the C terminal on the top on the casing shown in Figure 21; casing 1 lower terminal a, b, the c right-to-left number that links to each other with the terminal of motor; first, second terminal butt joint stop button TA; the external start button QA of second, third terminal; after the energized, open starter motor like this, then shut down by TA by QA.

Claims (2)

1, the solid-state contactor of three-phase power comprises that casing 1, Lian Ming mould radiator cover 2, radiator 3, circuit board 4 and by being serially connected in respectively on A, B, the C phase line, and structurally identical bidirectional thyristor BCR ₁, the capacitance-resistance absorption circuit, main loop circuit and control loop circuit that the loop constitutes are triggered in the overvoltage protection loop, it is characterized in that said circuits for triggering are by current-limiting resistance R ₂The back cross-over connection of connecting with the normally opened contact of vacuum switch j constitutes in anode and the trigger electrode two ends of twin crystal brake tube BCR1; The control loop circuit is by the overload detection coil J that is serially connected in respectively on A, B, the C phase line ₁, J ₂, J ₃, transformer B ₁, full-bridge rectifier D ₁, capacitor C ₄, coil J ₄, J ₅, resistance R ₇, controllable silicon CR, vacuum switch j, external manual control is opened, is stopped button QA, TA and forms overload detection magnet exciting coil J ₁, J ₂, J ₃Three normally opened contact J ₁, J ₃, J ₃, back in parallel one end is connected the other end with the control end of controllable silicon CR and is connected coil J with resistance 7 ₄The contact be normally opened contact, coil J ₅The contact be normally-closed contact.

2, the solid-state contactor of three-phase power according to claim 1 is characterized in that and can be provided with 3 respectively by resistance R on A, B, C phase line ₈, capacitor C ₅, resistance R ₉Capacitor C ₆, resistance R ₁₀, capacitor C ₇The capacitance-resistance absorption circuit that constitutes, and be connected into Y shape.

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