CN204118685U - Overvoltage and under-voltage protection tripper - Google Patents
Overvoltage and under-voltage protection tripper Download PDFInfo
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- CN204118685U CN204118685U CN201420519870.5U CN201420519870U CN204118685U CN 204118685 U CN204118685 U CN 204118685U CN 201420519870 U CN201420519870 U CN 201420519870U CN 204118685 U CN204118685 U CN 204118685U
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Abstract
Overvoltage and under-voltage protection tripper, comprise the sample circuit be connected with load power source, magnetictrip, also comprises under-voltage comparison circuit, overvoltage comparison circuit and reference circuit; Described reference circuit is connected with under-voltage comparison circuit and exports under-voltage reference voltage V b to under-voltage comparison circuit, be connected to overvoltage comparison circuit output overvoltage reference voltage V a with overvoltage comparison circuit, described sample circuit is connected with under-voltage comparison circuit and overvoltage comparison circuit respectively and exports sampled voltage Vc; The output of described under-voltage comparison circuit and overvoltage comparison circuit is connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively.Overvoltage of the present utility model and under-voltage protection tripper structure is simple, volume is little, cost is low.
Description
Technical field
The utility model relates to Low Voltage Electrical Apparatus, particularly a kind of release with overvoltage and under-voltage duplicate protection.
Background technology
Overvoltage or under-voltage may be produced because of the change of bulk loads in supply line, cause the damage of other power consumption equipment.Existing normally adopt overvoltage protection release and under-voltage protection tripper to ensure that power consumption equipment is operated in normal power supply state under.Under-voltage protection generally refers to that protective device cuts off supply line automatically when supply line's voltage is lower than a set point, and when line voltage distribution recovers normal by the time, protective device can manually be recovered again.Overvoltage protection generally refers to that protective device cuts off supply line automatically when line voltage distribution is more than a set point, and when line voltage distribution recovers normal by the time, protective device can manually be recovered again.
Mainly adopt an overvoltage protection release and a under-voltage protection tripper to realize overvoltage and under-voltage protection respectively to the overvoltage of supply line and under-voltage protection in the market, volume is comparatively large, and cost is higher.In addition, existing overvoltage and under-voltage protection are all powered to magnetictrip by special power supply circuits usually, when overvoltage detected or under-voltage after, realize by the electronic switch controlled on magnetictrip current supply circuit protection of threading off, circuit structure is complicated, and cost is high; Common electronic switching tube can be power switch pipe, triode, optocoupler etc.
Summary of the invention
The purpose of this utility model is the defect overcoming prior art, provides a kind of structure is simple, volume is little, cost is low overvoltage and under-voltage protection tripper.
For achieving the above object, the utility model have employed following technical scheme:
A kind of overvoltage and under-voltage protection tripper, comprise the sample circuit be connected with load power source, magnetictrip, also comprise under-voltage comparison circuit, overvoltage comparison circuit and reference circuit; Described reference circuit is connected with under-voltage comparison circuit and exports under-voltage reference voltage V b to under-voltage comparison circuit, be connected to overvoltage comparison circuit output overvoltage reference voltage V a with overvoltage comparison circuit, described sample circuit is connected with under-voltage comparison circuit and overvoltage comparison circuit respectively and exports sampled voltage Vc; The output of described under-voltage comparison circuit and overvoltage comparison circuit is connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively.
Further, also comprise power circuit, described reference circuit is connected with power circuit.
Further, the current supply circuit of described magnetictrip coil is provided with delay circuit.
Further, described sample circuit comprises diode VD1, and the positive pole of described diode VD1 is connected with the L pole of electric network source, and the negative pole of diode VD1 is connected with resistance R7 one end through resistance R3, resistance R7 other end ground connection; The positive pole of diode VD4 is connected with the connecting line between resistance R3 and resistance R7, and the negative pole of diode VD4 is connected with one end of electric capacity C2, the other end ground connection of electric capacity C2; One end ground connection that resistance R8 is in parallel with voltage-stabiliser tube VZ1, the other end is connected with the negative pole of diode VD4; The negative pole of diode VD4 is connected with under-voltage comparison circuit and overvoltage comparison circuit.
Further, described power circuit comprises rectifier bridge, and the L pole of electric network source is connected with two inputs of rectifier bridge respectively with N pole, is in series with resistance R1, electric capacity C1 between the L pole of electric network source and the input of rectifier bridge; The cathode output end ground connection of rectifier bridge, resistance R11 and R12 is parallel with between the cathode output end of rectifier bridge and cathode output end, the anode of reference power supply IC1 is connected with the cathode output end of rectifier bridge, the minus earth of reference power supply IC1, the reference edge of reference power supply IC1 is connected with the connecting line between resistance R11 and R12; The positive pole of electric capacity C5 is connected with the cathode output end of rectifier bridge, the minus earth of electric capacity C5.
Further, described reference circuit comprises the resistance R4, resistance R5, the resistance R6 that connect successively, resistance R4 one end is connected with the input of reference circuit, resistance R4 is connected output overvoltage reference voltage V a with the connecting line of resistance R5 with overvoltage comparison circuit, the connecting line of resistance R5 and resistance R6 is connected with under-voltage comparison circuit and exports under-voltage reference voltage V b, resistance R6 other end ground connection.
Further, described overvoltage comparison circuit comprises integrated circuit (IC) 2A, and under-voltage comparison circuit comprises integrated circuit (IC) 2B.
Further, described overvoltage comparison circuit comprises comparator, and under-voltage comparison circuit comprises comparator.
Further, the overvoltage reference voltage V a that electrode input end and the reference circuit of described integrated circuit (IC) 2A export is connected, and the sampled voltage Vc that negative input and sample circuit export is connected; The under-voltage reference voltage V b that electrode input end and the reference circuit of integrated circuit (IC) 2B export is connected, and the sampled voltage Vc that negative input and sample circuit export is connected; The output of integrated circuit (IC) 2A and the output of integrated circuit (IC) 2B are connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively; Diode VD5, resistance R9 is in series with between the output and magnetictrip coil of integrated circuit (IC) 2A.
Further, described overvoltage and under-voltage protection tripper also comprise surge absorbing circuit, and described surge absorbing circuit is connected with sample circuit and power circuit, and described surge absorbing circuit comprises the piezo-resistance RV1 be arranged between electric network source L pole and N pole.
Overvoltage of the present utility model and under-voltage protection tripper have overvoltage and under-voltage protection function simultaneously; and the output of under-voltage comparison circuit and overvoltage comparison circuit is connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively, structure is simple, volume is little, cost is low.
Accompanying drawing explanation
Fig. 1 is the principle schematic of the utility model overvoltage and under-voltage protection tripper;
Fig. 2 is the circuit diagram of the utility model overvoltage and under-voltage protection tripper.
Embodiment
Below in conjunction with the embodiment that accompanying drawing 1 to 2 provides, further illustrate the embodiment of overvoltage of the present utility model and under-voltage protection tripper.Overvoltage of the present utility model and under-voltage protection tripper are not limited to the description of following examples.
Overvoltage of the present utility model and under-voltage protection tripper, comprise the sample circuit be connected with load power source, magnetictrip, under-voltage comparison circuit, overvoltage comparison circuit and reference circuit; Described reference circuit is connected with under-voltage comparison circuit and exports under-voltage reference voltage V b to under-voltage comparison circuit, be connected to overvoltage comparison circuit output overvoltage reference voltage V a with overvoltage comparison circuit, described sample circuit is connected with under-voltage comparison circuit and overvoltage comparison circuit respectively and exports sampled voltage Vc; The output of described under-voltage comparison circuit and overvoltage comparison circuit is connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively.Overvoltage of the present utility model and under-voltage protection tripper have overvoltage and under-voltage protection function simultaneously, and overvoltage protection and under-voltage protection can common sparing electronic components.And the output of under-voltage comparison circuit and overvoltage comparison circuit is connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively, without the need to arranging independent power supply circuits for magnetictrip, structure is simple, volume is little, cost is low.The overvoltage reference voltage V a that described reference circuit exports and under-voltage reference voltage V b can directly be provided by the external circuit beyond release, as the electronic controller of circuit breaker, the reference voltage that outside provides directly can be exported to comparison circuit by reference circuit, exports to comparison circuit after also can carrying out dividing potential drop or voltage stabilizing process; Certainly also can arrange power circuit to realize in release inside.
As shown in Figure 1-2, overvoltage and under-voltage protection tripper comprise surge absorbing circuit, the power circuit be connected with surge absorbing circuit circuit and sample circuit, described power circuit comprises the reduction voltage circuit, rectification circuit and the filter circuit of pressure-stabilizing that connect successively, and described power circuit is connected with reference circuit; Described sample circuit is connected with under-voltage comparison circuit and overvoltage comparison circuit respectively and exports sampled voltage Vc; Described reference circuit is connected to overvoltage comparison circuit output overvoltage reference voltage V a with overvoltage comparison circuit, be connected export under-voltage reference voltage V b to under-voltage comparison circuit with under-voltage comparison circuit; The output of described under-voltage comparison circuit and overvoltage comparison circuit is connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively; The current supply circuit of described magnetictrip coil is provided with delay circuit.
Described power circuit, comprises rectifier bridge, and the L pole of electric network source is connected with two inputs of rectifier bridge respectively with N pole, is in series with resistance R1, electric capacity C1 between the L pole of electric network source and the input of rectifier bridge; The cathode output end ground connection of rectifier bridge, resistance R11 and R12 is parallel with between the cathode output end of rectifier bridge and cathode output end, the anode of reference power supply IC1 is connected with the cathode output end of rectifier bridge, the minus earth of reference power supply IC1, the reference edge of reference power supply IC1 is connected with the connecting line between resistance R11 and R12; The positive pole of electric capacity C5 is connected with the cathode output end of rectifier bridge, the minus earth of electric capacity C5, is also parallel with electric capacity C6 at electric capacity C5 two ends.Carry out full-wave rectification by the rectifier bridge comprising diode VD2, VD3 after the reduction voltage circuit resistance-capacitance depressurization that grid alternating current source is made up of resistance R1, electric capacity C1, described rectification circuit comprises rectifier bridge; Voltage stabilizing is carried out again by resistance R11, resistance R12, reference power supply IC1, electric capacity C5 carries out filtering to the power supply after voltage stabilizing, to give the 7.5V voltage vcc of circuit with stable, described filter circuit of pressure-stabilizing comprises resistance R11, resistance R12, reference power supply IC1, electric capacity C5, preferentially also comprises electric capacity C6.
Described sample circuit, comprises diode VD1, and the positive pole of diode VD1 is connected with the L pole of electric network source, and the negative pole of diode VD1 is connected with resistance R7 one end through resistance R2, resistance R3, resistance R7 other end ground connection; The positive pole of diode VD4 is connected with the connecting line between resistance R3 and resistance R7, and the negative pole of diode VD4 is connected with one end of electric capacity C2, the other end ground connection of electric capacity C2; One end ground connection that resistance R8 is in parallel with voltage-stabiliser tube VZ1, the other end is connected with the negative pole of diode VD4; The negative pole of diode VD4 is connected with under-voltage comparison circuit and overvoltage comparison circuit.Grid alternating current source is after diode VD1 halfwave rectifier, dividing potential drop is carried out by resistance R2, resistance R3, resistance R7, isolated by diode VD4, after electric capacity C2 filtering, acquisition one becomes the sampled voltage Vc in proportionate relationship with line voltage again, carries out under voltage and superpotential basis for estimation as under-voltage comparison circuit and overvoltage comparison circuit.Resistance R8 and voltage-stabiliser tube VZ1 carries out pincers pressure to sampled voltage Vc, protects too high sampled voltage Vc damage comparison circuit.
Described reference circuit, comprise the resistance R4, resistance R5, the resistance R6 that connect successively, resistance R4 one end is connected with the input of reference circuit, namely the voltage vcc exported with power circuit is connected, resistance R4 is connected output overvoltage reference voltage V a with the connecting line of resistance R5 with overvoltage comparison circuit, the connecting line of resistance R5 and resistance R6 is connected with under-voltage comparison circuit and exports under-voltage reference voltage V b, resistance R6 other end ground connection.The resistance R4 of reference circuit, resistance R5, resistance R6 carry out dividing potential drop to power Vcc, obtain overvoltage reference voltage V a and under-voltage reference voltage V b, carry out the judgment standard of overvoltage and under voltage as overvoltage comparison circuit and under-voltage comparison circuit.Reference circuit structure of the present utility model is simple, can provide overvoltage reference voltage V a and under-voltage reference voltage V b simultaneously.
Described overvoltage comparison circuit comprises integrated circuit (IC) 2A, and under-voltage comparison circuit comprises integrated circuit (IC) 2B.The overvoltage reference voltage V a that electrode input end and the reference circuit of integrated circuit (IC) 2A export is connected, and the sampled voltage Vc that negative input and sample circuit export is connected; The under-voltage reference voltage V b that electrode input end and the reference circuit of integrated circuit (IC) 2B export is connected, and the sampled voltage Vc that negative input and sample circuit export is connected; The output of integrated circuit (IC) 2A and the output of integrated circuit (IC) 2B are connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively; Diode VD5, resistance R9 is in series with between the output and magnetictrip coil of integrated circuit (IC) 2A.
Described delay circuit comprises the two ends being arranged on magnetictrip coil and is parallel with electric capacity C3 as delay circuit.When overvoltage comparison circuit and under-voltage comparison circuit do not provide maintenance electric current, provided the maintenance electric current of certain hour by an electric capacity C3, to realize the time delay of certain hour, improve the reliability of circuit.
Described surge absorbing circuit, comprises the piezo-resistance RV1 be arranged between electric network source L pole and N pole.Piezo-resistance RV1 is as surge absorbing circuit, and the surge voltage in protection electrical network is on the impact of this circuit.
Overvoltage of the present utility model and under-voltage protection tripper; when line voltage is normal; sampled voltage Vc is less than reference voltage V a; but be greater than reference voltage V b; integrated circuit (IC) 2A exports high level, integrated circuit (IC) 2B output low level, keeps electric current I 1 to be exported by integrated circuit (IC) 2A; flow back to integrated circuit (IC) 2B through the coil of diode VD5, resistance R9, magnetictrip KA, resistance R10, the coil of the magnetictrip KA magnetictrip KA after electric current that is maintained keeps attracting state.When line voltage is higher than setting threshold, sampled voltage Vc is greater than reference voltage V a, also reference voltage V b is greater than, integrated circuit (IC) 2A output low level, integrated circuit (IC) 2B is output low level also, the current supply circuit of magnetictrip coil cannot reoffer and keep electric current I 1, and the electric capacity C3 of delay circuit provides the maintenance electric current I 2 of certain hour, and coil magnetictrip KA after losing maintenance electric current I 2 of magnetictrip KA threads off.When line voltage is lower than setting threshold, sampled voltage Vc is less than reference voltage V a, also reference voltage V b is less than, integrated circuit (IC) 2A exports high level, integrated circuit (IC) 2B also exports high level, comparison circuit cannot reoffer and keep electric current I 1, and electric capacity C3 provides the maintenance electric current I 2 of certain hour, and magnetictrip KA threads off after losing maintenance electric current I 2.
The comparison circuit that the overvoltage comparison circuit of the present embodiment and under-voltage comparison circuit are formed, what adopt is the comparison of the sampled voltage that realizes of integrated circuit and reference voltage, can certainly adopt the discrete component that such as comprises comparator using build comparison circuit or with specialized voltages detector as comparison circuit.Filter circuit of pressure-stabilizing can adopt voltage stabilizing didoe or other voltage stabilizing circuit to carry out voltage stabilizing.
Above content is in conjunction with concrete preferred implementation further detailed description of the utility model, can not assert that concrete enforcement of the present utility model is confined to these explanations.For the utility model person of an ordinary skill in the technical field, without departing from the concept of the premise utility, some simple deduction or replace can also be made, all should be considered as belonging to protection range of the present utility model.
Claims (10)
1. overvoltage and a under-voltage protection tripper, comprises the sample circuit be connected with load power source, magnetictrip, it is characterized in that: also comprise under-voltage comparison circuit, overvoltage comparison circuit and reference circuit; Described reference circuit is connected with under-voltage comparison circuit and exports under-voltage reference voltage V b to under-voltage comparison circuit, be connected to overvoltage comparison circuit output overvoltage reference voltage V a with overvoltage comparison circuit, described sample circuit is connected with under-voltage comparison circuit and overvoltage comparison circuit respectively and exports sampled voltage Vc; The output of described under-voltage comparison circuit and overvoltage comparison circuit is connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively.
2. overvoltage according to claim 1 and under-voltage protection tripper, is characterized in that: also comprise power circuit, described reference circuit is connected with power circuit.
3. overvoltage according to claim 1 and under-voltage protection tripper, is characterized in that: the current supply circuit of described magnetictrip coil is provided with delay circuit.
4. overvoltage according to claim 1 and under-voltage protection tripper, it is characterized in that: described sample circuit comprises diode VD1, the positive pole of described diode VD1 is connected with the L pole of electric network source, and the negative pole of diode VD1 is connected with resistance R7 one end through resistance R3, resistance R7 other end ground connection; The positive pole of diode VD4 is connected with the connecting line between resistance R3 and resistance R7, and the negative pole of diode VD4 is connected with one end of electric capacity C2, the other end ground connection of electric capacity C2; One end ground connection that resistance R8 is in parallel with voltage-stabiliser tube VZ1, the other end is connected with the negative pole of diode VD4; The negative pole of diode VD4 is connected with under-voltage comparison circuit and overvoltage comparison circuit.
5. overvoltage according to claim 2 and under-voltage protection tripper, it is characterized in that: described power circuit comprises rectifier bridge, the L pole of electric network source is connected with two inputs of rectifier bridge respectively with N pole, is in series with resistance R1, electric capacity C1 between the L pole of electric network source and the input of rectifier bridge; The cathode output end ground connection of rectifier bridge, resistance R11 and R12 is parallel with between the cathode output end of rectifier bridge and cathode output end, the anode of reference power supply IC1 is connected with the cathode output end of rectifier bridge, the minus earth of reference power supply IC1, the reference edge of reference power supply IC1 is connected with the connecting line between resistance R11 and R12; The positive pole of electric capacity C5 is connected with the cathode output end of rectifier bridge, the minus earth of electric capacity C5.
6. overvoltage according to claim 1 and 2 and under-voltage protection tripper; it is characterized in that: described reference circuit comprises the resistance R4, resistance R5, the resistance R6 that connect successively; resistance R4 one end is connected with the input of reference circuit; resistance R4 is connected output overvoltage reference voltage V a with the connecting line of resistance R5 with overvoltage comparison circuit; the connecting line of resistance R5 and resistance R6 is connected with under-voltage comparison circuit and exports under-voltage reference voltage V b, resistance R6 other end ground connection.
7. overvoltage according to claim 1 and under-voltage protection tripper, is characterized in that: described overvoltage comparison circuit comprises integrated circuit (IC) 2A, and under-voltage comparison circuit comprises integrated circuit (IC) 2B.
8. overvoltage according to claim 1 and under-voltage protection tripper, is characterized in that: described overvoltage comparison circuit comprises comparator, and under-voltage comparison circuit comprises comparator.
9. overvoltage according to claim 7 and under-voltage protection tripper, is characterized in that: the overvoltage reference voltage V a that electrode input end and the reference circuit of described integrated circuit (IC) 2A export is connected, and the sampled voltage Vc that negative input and sample circuit export is connected; The under-voltage reference voltage V b that electrode input end and the reference circuit of integrated circuit (IC) 2B export is connected, and the sampled voltage Vc that negative input and sample circuit export is connected; The output of integrated circuit (IC) 2A and the output of integrated circuit (IC) 2B are connected to form the current supply circuit of magnetictrip coil with the two ends of magnetictrip coil respectively; Diode VD5, resistance R9 is in series with between the output and magnetictrip coil of integrated circuit (IC) 2A.
10. overvoltage according to claim 2 and under-voltage protection tripper; it is characterized in that: described overvoltage and under-voltage protection tripper also comprise surge absorbing circuit; described surge absorbing circuit is connected with sample circuit and power circuit, and described surge absorbing circuit comprises the piezo-resistance RV1 be arranged between electric network source L pole and N pole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420519870.5U CN204118685U (en) | 2014-09-11 | 2014-09-11 | Overvoltage and under-voltage protection tripper |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420519870.5U CN204118685U (en) | 2014-09-11 | 2014-09-11 | Overvoltage and under-voltage protection tripper |
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| Publication Number | Publication Date |
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| CN204118685U true CN204118685U (en) | 2015-01-21 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201420519870.5U Active CN204118685U (en) | 2014-09-11 | 2014-09-11 | Overvoltage and under-voltage protection tripper |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104242232A (en) * | 2014-09-11 | 2014-12-24 | 浙江正泰电器股份有限公司 | Overvoltage and undervoltage protection tripping device |
| CN107658844A (en) * | 2017-11-07 | 2018-02-02 | 浙江颐顿机电有限公司 | A kind of single-phase input voltage owes overprotection circuit |
-
2014
- 2014-09-11 CN CN201420519870.5U patent/CN204118685U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104242232A (en) * | 2014-09-11 | 2014-12-24 | 浙江正泰电器股份有限公司 | Overvoltage and undervoltage protection tripping device |
| CN107658844A (en) * | 2017-11-07 | 2018-02-02 | 浙江颐顿机电有限公司 | A kind of single-phase input voltage owes overprotection circuit |
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