CN2066207U - Low-current drain alternating current overcurrent break device - Google Patents

Abstract

The utility model discloses an over-current break device with low-current consumption and high sensitivity. A current/voltage converter is used for detecting the current quantity of an electric device. If the current quantity of the electric device overtakes the setting value, the over-value signal is conveyed into a delay circuit. After the delay time, the current quantity is judged whether is a long-period action. If the current quantity is not the long-period action, the device makes current still. If the current quantity is the long-period action, the device cuts the power supply of the user. If the device wants to be reset to supply the electricity for the user over again, the electric switch of the user is opened after closing. The device makes current. At the moment, if the load excesses the quantity, the device is cut over again. If the load is smaller than the setting value, the device supplies the electricity normally.

Description

Low-current drain alternating current overcurrent break device

The present utility model is a kind of low power consuming, and highly sensitive interchange overcurrent breaker device belongs to the electronic apparatus class.Existing interchange overcurrent breaker device has electromagnetism-mechanical type, electric heating-mechanical type, and electronic type.Electromagnetism-mechanical shortcoming is the identification overcurrent to be long-term action or acts and efforts for expediency.Electric heating-mechanical shortcoming is influenced by ambient temperature big, and sensitivity is low, and the resetting means of the two all is installed on the breaker device, can not reset at a distance, and the shortcoming of electronic type is to want extra power consumption, and the circuit complexity.

It is a kind of stable that the present utility model provides, high sensitivity, and circuit is simple, low power consumption, antijamming capability is strong, and reset mode is the alternating current breaker device simply and easily.It both had been widely used for apartment, quarters for the single, office and had made electricity-limiter, can make the repeated protective device of various instrument and equipments and the overload of loss of phase protector of threephase motor again.

Of the present utility model being characterised in that: by current detection circuit, step-down rectifying circuit, anti-disturbance circuit, delay switch circuit and circuit breaker action holding circuit are formed.

Figure (1) exchanges the circuit theory diagrams of overcurrent breaker device for the present utility model low power consumption.In figure (1), mains supply is inserted by 1,2 two ends, user's load (or power consumption equipment) R ₃Pick out by 3,4 two ends.When user's's (or power consumption equipment) power consumption was lower than set point, the electricity of electrical network was by the normally closed interlock J of 1 end and 2 ends process relay ₁With movable contact J ₃And current-to-voltage converter L ₂, again by 3 ends and 4 ends to load R ₃Normal power supply.Flow through load R ₃The magnitude of current by current-to-voltage converter L ₂And L ₃Be transformed into proportional with it alternating voltage, again input rectifier D ₅Ac input end, D ₅The pulsating dc voltage of dc output end output be added in capacitor C ₃And resistance R ₄, R ₅, R ₆On carry out integration, capacitor C ₃On voltage swing with flow through load R ₃On magnitude of current size and duration relevant, this voltage also is added in by resistance R simultaneously ₄And R ₅On the branch road of series connection, and in resistance R ₄Dividing potential drop of last generation, R ₄The voltage at two ends also is added in transistor T simultaneously ₂Base stage and emitter on, as load R ₃On electric current during less than set point, R ₄The voltage at two ends is to be lower than transistor T ₂Turn-on voltage, when flowing through load R ₃On electric current surpass set point, capacitor C ₃On magnitude of voltage will rise in time.If load R ₃On the excess electric current be long-term action, capacitor C then ₃On voltage when being raised to certain value, resistance R ₄The voltage at two ends will be higher than transistor T ₂Conducting voltage, transistor T ₂Conducting, capacitor C ₃The voltage at two ends is through transistor T ₂The e utmost point, the c utmost point removes to trigger controllable silicon T ₁, controllable silicon T ₁Conducting.T ₁After the conducting, supply voltage is through capacitor C ₁After the step-down, be added on by diode D ₁, D ₂, D ₃, D ₄The converter input of the bridge rectifier of forming, the direct voltage of its dc output end output is added in the magnet exciting coil L of relay ₁Two ends, the actuating of relay, armature contact leaves normally-closed contact J ₁, and contact normally opened contact J ₂Thereby cut off electrical network and supplied with user load R ₃Power supply.At this moment, though load R ₃On electric current reduce to make transistor T ₂Again end, make controllable silicon T ₁Close, but because the normally opened contact of relay is to be connected on by D ₁, D ₂, D ₃, D ₄The ac input end of forming rectifier bridge, supply voltage by 1 end through capacitor C ₁, rectifier bridge D ₁, D ₂, D ₃, D ₄, the normally opened contact J of relay ₂, armature contact J ₃, load resistance R ₃Form path, relay coil L to 2 ends again ₁Two ends voltage is arranged, make circuit breaker be in the action hold mode, thereby make load R ₃On lose due voltage.In figure (1), resistance R ₁Effect be the C that releases ₁The electric charge of last storage is in case produce over-voltage breakdown controllable silicon, resistance R ₂Be controllable silicon T ₁Current-limiting protection resistance, its effect is to prevent at T ₁The moment of conducting, produce overcurrent and damage T ₂, C ₁Effect have two kinds, wherein one is to make filter capacitor, it two is to prevent controllable silicon T ₁Because of making relay misoperation, the interference signal triggering and conducting does.

If flow through load R ₃On the excess electric current be acts and efforts for expediency, C ₃On voltage will rise in time, also be not raised to as this magnitude of voltage and can make transistor T ₂Conducting the time, load R ₃On the excess electric current just disappear C ₃On voltage can not rise crystal T again ₂Not conducting, controllable silicon T ₁Be in closed condition, relay is failure to actuate, and this device still powers to the load.

After the interchange overcurrent device outage action of low power consumption, if this device is resetted again to load R ₃Power supply need only after (as 4 ends or 3 ends on the figure (1)) excision connect load from circuit again.Because because of load R ₃The excision and lost exciting voltage, relay resets again, armature contact J ₃Connect normally closed interlock J again ₁Recover again to load R ₃Power supply.

Accompanying drawing (1) illustrates:

D ₁, D ₂, D ₃, D ₄Diode

J ₁Relay normally open contact

J ₂The relay normally-closed contact

J ₃The relay armature contact

R ₁, R ₂, R ₃, R ₄, R ₅, R ₆Be resistor

C ₁, C ₂, C ₃Be capacitor

L ₁Relay excitation coil

L ₂Current-to-voltage converter is elementary

L ₃Current-to-voltage converter is secondary

T ₁Bidirectional triode thyristor

T ₂NPN type triode

D ₅Rectifier

Claims (5)

1, a kind of low power consumption, highly sensitive interchange overcurrent breaker device is characterized in that: it is by current detection circuit, capacitor step-down rectifier circuit, circuit breaker action holding circuit, delay switch circuit is formed.

2, device according to claim 1, being characterized as of its current detection circuit: two coils on the magnetisable material, L ₂And L ₃, primary coil L ₂Be connected in series secondary coil L mutually with load ₃Then insert rectifying device D ₅Two ac input ends.

3, device according to claim 1, being characterized as of the circuit of its delay switch: by capacitor C ₃, resistor R ₄And R ₅, R ₆, transistor T ₂With controllable silicon T ₁Form capacitor C ₃Series resistance R ₆After respectively with rectifying device D ₅Two dc output ends link resistance R ₄And R ₅After the series connection again with capacitor C ₃Be in parallel C ₃And R ₅An end that links and controllable silicon T ₁Negative electrode link C ₃And R ₄The end and the transistor T that link ₂Emitter link R ₄And R ₅The end and the transistor T that join ₂Base stage link transistor T ₂Collector electrode and controllable silicon T ₁Gate pole (grid) join.

4, being characterized as according to claim 1 or 3 its step-down rectifying circuits: by capacitor C ₁, resistor R ₁, R ₂, rectifier diode D ₁, D ₂, D ₃, D ₄Form capacitor C ₁And resistor R ₁After the parallel connection, 1 end of termination electric current input, the other end is connected to by rectifier diode D ₁, D ₂, D ₃, D ₄An ac input end of the full-wave rectification bridge of forming, full-wave rectification bridge D ₁, D ₂, D ₃, D ₄Another ac input end and resistance R ₂Series connection back and controllable silicon T ₁Anode link controllable silicon T ₁Negative electrode and power supply import 2 ends and join.

5, according to the device of claim 1, being characterized as of its actuating of relay holding circuit: by capacitor C ₂, relay excitation coil L ₁, relay normally-closed contact J ₁, relay normally open contact J ₂With relay armature contact J ₃Form.Capacitor C ₂With relay excitation coil L ₁After being in parallel, insert full-wave rectification bridge D ₁, D ₂, D ₃, D ₄Two dc output ends, relay normally-closed contact and power supply are imported 1 end and are linked.Relay normally open contact and resistance R ₂Link the primary coil L of relay armature contact and current detector with the ac input end of the full-wave rectification bridge contact place that links ₂The series connection back is exported 3 ends with load and is linked.