CN201204570Y

CN201204570Y - AC contactless control switch

Info

Publication number: CN201204570Y
Application number: CNU2008200550656U
Authority: CN
Inventors: 刘成龙; 许成; 王展英
Original assignee: SHANGHAI ZHIDA ELECTRONIC CO Ltd
Current assignee: SHANGHAI ZHIDA ELECTRONIC CO Ltd
Priority date: 2008-01-24
Filing date: 2008-01-24
Publication date: 2009-03-04
Anticipated expiration: 2018-01-24

Abstract

The utility model discloses an alternating non-contact control switch, comprising a load electricity supply main loop, a power source module, electronic switches and current inductors connected in series in the main loop in sequence, a default phase detection module and a resistance-capacitance absorbing module connected in parallel in each phase of the main loop, a microprocessor, a control signal amplifying module, a current voltage converting module, a state display module, an information input module and a relay that conducts and cuts off the electronic switches; the current inductors set in the main loop and the default phase detection module collect default, overheat and instantaneous release signals in the main loop and inputs them to the microprocessor, then outputs the control signal after signal process, the control driving the relay to move to conduct or cut off the electronic switches, as well as display operation state of the main loop and set the overheat and instantaneous release values for the main loop through the state display module and the information input module; the control switch can control operation of the load safely, having functions of default, overheat and instantaneous overflow protection for the control switch.

Description

Exchange contactless control switch

Technical field

The utility model relates to the control switch of power consumption equipment in the alternating current circuit, relates in particular to the contactless control switch of power consumption equipment in a kind of alternating current circuit.

Background technology

At present in low voltage control system, usually adopt A.C. contactor to come starting or stoping of control apparatus equipment in the alternating current circuit, for example adopt starting or stoping of A.C. contactor control AC asynchronous motor, its contact to A.C. contactor has certain requirement, needs to guarantee that the electric property of ac contactor contact is good; Special in the control of hoisting equipment heavy-duty motor, because electric motor starting is frequent, the as easy as rolling off a log faults such as ac contactor contact arcing, contact adhesion that cause; The ac contactor contact arcing causes poor contact of contacts, and long-time the use caused the motor phase shortage, the serious motor that burns; The ac contactor contact adhesion causes the motor phase fault, thereby causes electrical fault; Therefore, in the AC control circuit of this kind equipment, A.C. contactor just must be changed in use for some time, to guarantee the normal operation of motor and equipment; This A.C. contactor is short useful life, and has the potential safety hazard that causes electrical fault.And conventional A.C. contactor does not have thermal overload and instant over current protection function, and the thermal overload and the instantaneous overcurrent of protection motor must add thermal relay at home and abroad at control circuit.

Summary of the invention

Technical problem to be solved in the utility model provides the contactless control switch of a kind of interchange, the operation of its energy effective and safe ground control load in low voltage control system, and load is had the function of phase shortage, thermal overload and instantaneous overcurrent protection.

For solving the problems of the technologies described above, the utility model exchanges contactless control switch and comprises the electric major loop, the power module of control circuit also comprises the electronic switch summation current transformer that is series at successively in the described major loop, is parallel to first, second and the 3rd relay that each alternate open phase detection module of described major loop and capacitance-resistance absorb module, microprocessor, control signal amplification module, current/voltage modular converter, state display module, MIM message input module and control described electronic switch conducting or close;

Described power module opens and closes signal circuit by control module power supply circuits and electronic switch and forms, described power supply circuits provide working power to each control module respectively, the signal that described signal circuit provides electronic switch to open and close, described current transformer connects described current/voltage modular converter, the output signal of described current/voltage modular converter and open phase detection module is imported described microprocessor, described state display module is connected described microprocessor with MIM message input module, the output signal of described microprocessor connects described control signal amplification module;

The pull-in winding of described first relay connects described power supply circuits, the pull-in winding of described second relay connects described signal circuit, the pull-in winding of described the 3rd relay connects described control signal amplification module, the contact in turn series connection of described first, second and the 3rd contactor, the one end connects the control end of described electronic switch, and the other end connects described power supply circuits.

Above-mentioned power supply circuits input is 220V, and output is respectively 12V and 5V; Described signal circuit input is 220V, and output is 24V.

But above-mentioned electronic switch thyristor.Above-mentioned open phase detection module comprises lack detection circuit, photoelectric isolating circuit and logic level output circuit.Above-mentioned capacitance-resistance absorbs module and is made up of power resistor and capacitances in series.Above-mentioned state display module is made up of three 7 charactrons.Above-mentioned MIM message input module is a data entry keyboard.

Because the contactless control switch of interchange of the present utility model has adopted technique scheme, promptly adopt electronic switch to replace ac contactor contact, by be arranged at current transformer in the major loop and open phase detection module gather phase shortage in the major loop, overheated and wink moving signal and input microprocessor in after signal processing, export control signal, this control signal is amplified the rear drive actuating of relay to cut off the circuit of electronic switch controling end through amplification module, reaches the disconnection of electronic switch; Can show the running status of major loop and can move value by state display module and MIM message input module simultaneously and be provided with the overheated and wink of major loop; Therefore this exchanges the operation of contactless control switch energy effective and safe ground control load, and it has the function of phase shortage, thermal overload and instantaneous overcurrent protection to load.

Description of drawings

The utility model is described in further detail below in conjunction with drawings and embodiments:

Fig. 1 exchanges the schematic block circuit diagram of contactless control switch for the utility model.

Embodiment

As shown in Figure 1, the utility model exchanges the control that the alternative common A.C. contactor of contactless control switch is used for heavy-duty motor, electric heater etc.This control switch comprises the main circuit power supply 1 of motor 15, the power module of control circuit also comprises electronic switch 3 summation current transformers 4 that are series at successively in the described major loop 1, is parallel to first relay 12, second relay 13 and the 3rd relay 14 that described major loop 1 each alternate open phase detection module 5 and capacitance-resistance absorb module 6, microprocessor, control signal amplification module 8, current/voltage modular converter 9, state display module 10, MIM message input module 11 and control described electronic switch 3 conductings or close;

Described power module opens and closes signal circuit 22 by control module power supply circuits 21 and electronic switch and forms, described power supply circuits 21 provide working power to each control module of this control switch inside respectively, described signal circuit 22 provides the switching signal of electronic switch 3, described current transformer 4 connects described current/voltage modular converter 9, the output signal of described current/voltage modular converter 9 and open phase detection module 5 is imported described microprocessor 7, described state display module 10 is connected described microprocessor 7 with MIM message input module 11, the output signal of described microprocessor 7 connects described control signal amplification module 8;

The pull-in winding of described first relay 12 connects described power supply circuits 21, working properly as power supply circuits 21, represent that inner each control module of this control switch gets, then contact 121 adhesives of first relay 12, the pull-in winding of described second relay 13 connects described signal circuit 22, signal circuit 22 is given the signal of this control switch closure of sening as an envoy to, make contact 131 adhesives of second relay 13, the pull-in winding of described the 3rd relay 14 connects described control signal amplification module 8, its contact 141 is a normally-closed contact, in case in the major loop 1 phase shortage takes place, overheated or wink is when moving, sending signal after microprocessor 7 is handled makes the normally-closed contact 141 of the 3rd relay 14 open, described first relay 12, the contact in turn series connection of second relay 13 and the 3rd relay 14, the one end connects the control end of described electronic switch 3, and the other end connects described power supply circuits 21.During this control switch operate as normal; the contact of first relay 12, second relay 13 and the 3rd relay 14 is all closed; the control end of electronic switch 3 gets electronic switch 3 conductings of electric back; motor 15 normally moves; in case the contact of a relay is arranged for a certain reason opens; then after the electronic switch 3 control end dead electricity; electronic switch 3 turn-offs; cut off the motor 15 of major loop; being implemented in the operation of effective and safe ground control load in the low voltage control system, and load had the function of phase shortage, thermal overload and instantaneous overcurrent protection.

Above-mentioned power supply circuits 21 inputs are 220V, and output is respectively 12V and 5V; Described signal circuit 22 inputs are 220V, and output is 24V.

Above-mentioned electronic switch 3 is thyristor.Above-mentioned open phase detection module 5 comprises lack detection circuit, photoelectric isolating circuit and logic level output circuit.Above-mentioned capacitance-resistance absorbs module 6 and is made up of power resistor and capacitances in series.Above-mentioned state display module 10 is made up of three 7 charactrons.Above-mentioned MIM message input module 11 is data entry keyboards.

Because this control switch has adopted microprocessor, can realize accurate processing to acquired signal, also can be provided with by the parameter of input keyboard to required control, therefore this control switch has the inverse time lag function of thermal overload protection, the thermal overload operating current is pressed the rated current of 1.01 ~ 1.15 times in motor and is selected, and by input keyboard the data input microprocessor is set; When current of electric reaches 1.5 times of set points, the 3rd relay time-delay action in 20 seconds; When motor current reaches 2 times of set points, the 3rd relay time-delay action in 5 seconds; Cut off the control circuit of electronic switch, electronic switch turn-offs, and cuts off load and plays a protective role.Electric current more the big-movement time short more, realize the anti-time limit characteristic of this control switch load protection.Show " 0L " thermal overload symbol by display module simultaneously.

When control load is short-circuited, the 3rd relay instantaneous operation, the control circuit of cut-out electronic switch, electronic switch turn-offs, and cuts off external load circuit, shows " 0C " overcurrent symbol by display module simultaneously.The overcurrent protection operating value can be made as the rated current of 4 times in motor.

Be provided with the phase shortage electric circuit inspection, when the three-phase input voltage phase shortage, pass through lack detection circuit, light-coupled isolation makes microprocessor can obtain low level signal, microprocessor sends signal and makes the 3rd actuating of relay, cut off the control circuit of electronic switch, electronic switch turn-offs, and shows " LP " phase shortage symbol by display module simultaneously.

The protection of the power supply circuits of inner each control module of this control switch is finished with first relay, and the 12V power supply is the first relay adhesive just often, and when power supply broke down, first relay contact disconnected, and electronic switch is forbidden work.

Claims

1, the contactless control switch of a kind of interchange, comprise the electric major loop, the power module of internal control circuit is characterized in that: also comprise the electronic switch summation current transformer that is series at successively in the described major loop, be parallel to first, second and the 3rd relay that each alternate open phase detection module of described major loop and capacitance-resistance absorb module, microprocessor, control signal amplification module, current/voltage modular converter, state display module, MIM message input module and control described electronic switch conducting or close;

Described power module opens and closes signal circuit by internal control module power supply circuits and electronic switch and forms, described power supply circuits provide working power to each internal control module respectively, the signal that described signal circuit provides electronic switch to open and close, described current transformer connects described current/voltage modular converter, the output signal of described current/voltage modular converter and open phase detection module is imported described microprocessor, described state display module is connected described microprocessor with MIM message input module, the output signal of described microprocessor connects described control signal amplification module;

2, the contactless control switch of interchange according to claim 1 is characterized in that: described power supply circuits input is 220V, and output is respectively 12V and 5V; Described signal circuit input is 220V, and output is 24V.

3, the contactless control switch of interchange according to claim 1, it is characterized in that: described electronic switch is a thyristor.

4, the contactless control switch of interchange according to claim 1 is characterized in that: described open phase detection module comprises lack detection circuit, photoelectric isolating circuit and logic level output circuit.

5, the contactless control switch of interchange according to claim 1 is characterized in that: described capacitance-resistance absorbs module and is made up of power resistor and capacitances in series.

6, the contactless control switch of interchange according to claim 1 is characterized in that: described state display module is made up of three 7 charactrons.

7, the contactless control switch of interchange according to claim 1 is characterized in that: described MIM message input module is a data entry keyboard.