CN106159900A - A kind of protection circuit for carrying out current transformer function and protecting - Google Patents
A kind of protection circuit for carrying out current transformer function and protecting Download PDFInfo
- Publication number
- CN106159900A CN106159900A CN201610690920.XA CN201610690920A CN106159900A CN 106159900 A CN106159900 A CN 106159900A CN 201610690920 A CN201610690920 A CN 201610690920A CN 106159900 A CN106159900 A CN 106159900A
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- Prior art keywords
- circuit
- diode
- electric capacity
- audion
- current transformer
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/04—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers
- H02H7/042—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers for current transformers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The present invention discloses a kind of protection circuit for carrying out current transformer function and protecting; it is provided with ac input circuit, relay circuit, switching tube circuit, filter circuit, rectification circuit and protection coil circuit; described ac input circuit is connected with relay circuit; described relay circuit is connected with switching tube circuit; described switching tube circuit connects filter circuit; described filter circuit connects rectification circuit; described rectification circuit connects protection coil circuit, and described relay circuit controls to connect by the catalyst of protection circuit；In described protection coil circuit, it is provided with potentiometer W2, control coil L1 and controls switch KT；Relay circuit can be utilized to act on catalyst, make catalyst trip, thus cut off motor power, it is achieved overload protection, fast braking, open-phase protection.
Description
Technical field
The present invention relates to the field such as signal processing technology, protection circuit technology, specifically, be a kind of for carrying out electric current
The protection circuit of transformer function and protecting.
Background technology
Current transformer principle is based on what transformer principle was made.Current transformer is by the iron core closed and winding group
Become.Its first side winding number of turn is little, goes here and there in needing the circuit of electric current of measurement, and therefore it often has whole electricity of circuit
Stream flows through, and secondary side winding turn ratio is more, is serially connected in measuring instruments and protective loop, current transformer operationally, it
Secondary side circuit all the time be Guan Bi, therefore the impedance of measuring instruments and protective loop series coil is the least, current transformer
Duty close to short circuit.Current transformer is big for primary side electric current to be converted into secondary side small area analysis measure, secondary side
Can not open a way.
Current transformer principle is based on electromagnetic induction principle.Current transformer is by the iron core closed and winding group
Become.Its umber of turn is little, goes here and there in needing the circuit of electric current of measurement, and therefore it often has whole electric currents of circuit
Flowing through, Secondary Winding turn ratio is more, is serially connected in measuring instruments and protective loop, current transformer operationally, its two
Minor loop is Guan Bi all the time, and therefore the impedance of measuring instruments and protective loop series coil is the least, the work of current transformer
State is close to short circuit.
In the circuit of generating, power transformation, transmission of electricity, distribution and electricity consumption, size of current great disparity, has to several Wan An from several peaces.For
Being easy to measure, protect and control to need to be converted to the electric current that comparison is unified, additionally the voltage on circuit the most all compares Gao Ruzhi
It is breakneck for connecing measurement.Current transformer just plays current transformation and electrical isolation effect.
For the ammeter of pointer-type, the secondary current great majority of current transformer are ampere level (such as 5A etc.).For
Digital instrumentation, the signal of sampling is generally milliampere level (0-5V, 4-20mA etc.).Micro-transformer of current secondary current is milliampere
Level, acts primarily as the function served as bridge between big transformer and sampling.
Micro-transformer of current also has people referred to as " instrument current transformer ".(" instrument current transformer " has one layer to contain
Justice is the many current ratio precision current transformer used at laboratory, is generally used for expanding instrument range.)
Current transformer and transformer's type like being the most also to work according to electromagnetic induction principle, being voltage of transformator conversion and electric current is mutual
Sensor conversion is electric current.Current transformer connects the winding (number of turn is N1) of tested electric current, referred to as one time winding (or former limit
Winding, armature winding)；The winding (number of turn is N2) connecing measuring instruments is referred to as Secondary Winding (or vice-side winding, secondary windings).
Current transformer once winding current I1 and the current ratio of Secondary Winding I2, make actual current compare K.Current transformer
Current ratio when working under rated current, current transformer rated transformation ratio, represents with Kn.
Kn=I1n/I2n, the effect of current transformer (Current transformer is called for short CT) is can numerical value relatively
Big primary current is converted to, by certain no-load voltage ratio, the secondary current that numerical value is less, is used for carrying out protecting, the purposes such as measurement.As
No-load voltage ratio is the current transformer of 400/5, the electric current that reality is 400A can be changed into the electric current of 5A.
Summary of the invention
It is an object of the invention to provide a kind of protection circuit for carrying out current transformer function and protecting, it is possible to utilize
Relay circuit acts on catalyst, makes catalyst trip, thus cuts off motor power, it is achieved overload protection, quickly make
Dynamic, open-phase protection.
The present invention is achieved through the following technical solutions: a kind of protection circuit for carrying out current transformer function and protecting,
It is provided with ac input circuit, relay circuit, switching tube circuit, filter circuit, rectification circuit and protection coil circuit, described
Ac input circuit is connected with relay circuit, and described relay circuit is connected with switching tube circuit, described switching tube electricity
Road connects filter circuit, and described filter circuit connects rectification circuit, and described rectification circuit connects protection coil circuit, described relay
Device circuit controls to connect by the catalyst of protection circuit；It is provided with potentiometer W2, control coil in described protection coil circuit
L1 and control switch KT, first end of described control coil L1 switchs first end and the first of potentiometer W2 of KT with control respectively
Fixing end is connected, and the fixing end of the second of described potentiometer switchs second end and the second of control coil L1 of KT with control respectively
End is connected, and the fixing end of the first of described potentiometer W2 and second is fixed end and is all connected on the DC output end of rectification circuit.
The most to better implement the present invention, following set-up mode is used especially: on described ac input circuit
Being provided with resistance R1, electric capacity C1, electric capacity C3 and diode D1, first end of described electric capacity C1 is connected with first end of resistance R1
And be connected with alternating current power supply, second end of described electric capacity C1 be connected with second end of resistance R1 and with the positive pole of diode D1
Being connected, the negative pole of diode D1 is connected with first end of electric capacity C3 and is connected with relay circuit, described electric capacity C3's
Second end is connected with alternating current power supply and switching tube circuit respectively.
The most to better implement the present invention, following set-up mode is used especially: set in described relay circuit
Be equipped with electric capacity C2, relay K A and diode D2, the first end of described relay K A respectively with the first end, the diode of electric capacity C2
The negative pole of D1, the negative pole of diode D2 and switching tube circuit are connected；Second end of described relay K A connects electric capacity C2 respectively
The second end, the positive pole of diode D2 and switching tube circuit be connected, described relay K A control connect control switch KT.
The most to better implement the present invention, following set-up mode is used especially: set in described switching tube circuit
Being equipped with resistance R2, audion Q2, audion Q1 and potentiometer W1, first end of resistance R2 is connected with the negative pole of diode D2,
Second end of resistance R2 is connected with the colelctor electrode of audion Q2, and the base stage of audion Q2 is connected with filter circuit, audion
The emitter stage of Q2 is connected with the base stage of audion Q1, and the colelctor electrode of audion Q1 is connected with the positive pole of diode D2, three poles
The emitter stage of pipe Q1 is fixed end with the first of potentiometer W1 and is connected, the fixing end of the second of potentiometer W1 respectively with the of electric capacity C3
Two ends are connected with filter circuit.
The most to better implement the present invention, following set-up mode is used especially: be provided with in described filter circuit
First end of resistance R3 and electric capacity C4, resistance R3 is connected with the base stage of audion Q2, second end of electric capacity R3 respectively with electric capacity
First end of C4 is connected with the ac input end of rectification circuit, second end of electric capacity C4 respectively with rectification circuit exchange input
End is fixed end with the second of potentiometer W1 and is connected.
The most to better implement the present invention, following set-up mode is used especially: be provided with in described rectification circuit
The positive pole of diode D3, diode D4, diode D5 and diode D6, diode D3 and diode D6 be connected and with resistance R3
The second end be connected, the negative pole of diode D4 is connected with the negative pole of diode D5 and is connected with second end of electric capacity C4,
The negative pole of diode D3 is connected with the positive pole of diode D4 and fixes end with the second of potentiometer W2 and is connected, diode D5's
Positive pole is connected with the negative pole of diode D6 and fixes end with the first of potentiometer W2 and is connected.
The most to better implement the present invention, following set-up mode is used especially: described diode D3, diode
D4, diode D5 and diode D6 all use IN4004 diode.
The most to better implement the present invention, following set-up mode is used especially: described resistance R1 uses 500K's
Chip-R, described electric capacity C1 uses the patch capacitor of 0.22 μ F, described electric capacity C3 to use the electrochemical capacitor of 100 μ F, and electric capacity
The positive pole of C3 is connected with the negative pole of diode D1, and described diode D1 uses IN4007 diode.
The most to better implement the present invention, following set-up mode is used especially: described electric capacity C2 uses 47 μ F's
Electrochemical capacitor, and the positive pole of electric capacity C2 is connected with the negative pole of diode D1, described diode D2 uses 2CP12 diode.
The most to better implement the present invention, following set-up mode is used especially: described resistance R2 uses 24K paster
Resistance, described audion Q2 uses 3DG6 audion, and described audion Q1 uses 3DG130 audion, and described potentiometer W1 uses
200 ohm of potentiometers.
The present invention compared with prior art, has the following advantages and beneficial effect:
The present invention can utilize relay circuit to act on catalyst, makes catalyst trip, thus cuts off motor power, real
Existing overload protection, fast braking, open-phase protection.
The present invention arranges potentiometer in switching tube circuit, it is possible to according to different loads overpressure situation, carry out switching tube
The regulation of make-and-break voltage so that when whole circuit carries out current transformer protection, better.
Accompanying drawing explanation
Fig. 1 is the circuit theory diagrams of the present invention.
Detailed description of the invention
Below in conjunction with embodiment, the present invention is described in further detail, but embodiments of the present invention are not limited to this.
Embodiment 1:
A kind of protection circuit for carrying out current transformer function and protecting, it is possible to utilize relay circuit to act on catalyst
On, make catalyst trip, thus cut off motor power, it is achieved overload protection, fast braking, open-phase protection, as it is shown in figure 1,
It is specifically arranged to following structure: be provided with ac input circuit, relay circuit, switching tube circuit, filter circuit, rectification circuit
And protection coil circuit, described ac input circuit is connected with relay circuit, described relay circuit and switching tube circuit
Being connected, described switching tube circuit connects filter circuit, and described filter circuit connects rectification circuit, and described rectification circuit connects to be protected
Protective ring circuit, described relay circuit controls to connect by the catalyst of protection circuit；Arrange in described protection coil circuit
Have potentiometer W2, control coil L1 and control switch KT, first end of described control coil L1 respectively with control the of switch KT
One end is fixed end with the first of potentiometer W2 and is connected, and the fixing end of the second of described potentiometer switchs the second of KT with control respectively
End is connected with second end of control coil L1, and the fixing end of the first of described potentiometer W2 and second is fixed end and is all connected to rectification
On the DC output end of circuit, preferred potentiometer W2 uses the potentiometer of 220 ohm, and regulates and make the voltage of inductance L1 to be
1！~ 2V so that switching tube circuit is in reliable cut-off state.
Embodiment 2:
The present embodiment is to optimize further on the basis of above-described embodiment, the most to better implement the present invention, such as Fig. 1
Shown in, use following set-up mode especially: on described ac input circuit, be provided with resistance R1, electric capacity C1, electric capacity C3 and two
Pole pipe D1, first end of described electric capacity C1 is connected with first end of resistance R1 and same alternating current power supply (220v alternating current) is connected
Connecing, second end of described electric capacity C1 is connected with second end of resistance R1 and is connected with the positive pole of diode D1, diode D1
Negative pole be connected with first end of electric capacity C3 and be connected with relay circuit, second end of described electric capacity C3 respectively with exchange
Power supply is connected with switching tube circuit.
Embodiment 3:
The present embodiment is to optimize further on the basis of any of the above-described embodiment, the most to better implement the present invention,
As it is shown in figure 1, use following set-up mode especially: be provided with electric capacity C2, relay K A and two poles in described relay circuit
Pipe D2, the first end of described relay K A respectively with first end of electric capacity C2, the negative pole of diode D1, the negative pole of diode D2 and
Switching tube circuit is connected；Second end of described relay K A connect respectively second end of electric capacity C2, the positive pole of diode D2 and
Switching tube circuit is connected, and described relay K A controls to connect and controls to switch KT.
Embodiment 4:
The present embodiment is to optimize further on the basis of any of the above-described embodiment, the most to better implement the present invention,
As it is shown in figure 1, use following set-up mode especially: be provided with resistance R2, audion Q2, audion in described switching tube circuit
First end of Q1 and potentiometer W1, resistance R2 is connected with the negative pole of diode D2, and second end of resistance R2 is with audion Q2's
Colelctor electrode is connected, and the base stage of audion Q2 is connected with filter circuit, the emitter stage of audion Q2 and the base stage of audion Q1
Being connected, the colelctor electrode of audion Q1 is connected with the positive pole of diode D2, the of the emitter stage of audion Q1 and potentiometer W1
One fixes end is connected, and the fixing end of the second of potentiometer W1 is connected with the second end and the filter circuit of electric capacity C3 respectively.
Embodiment 5:
The present embodiment is to optimize further on the basis of any of the above-described embodiment, the most to better implement the present invention,
As it is shown in figure 1, use especially following set-up mode: be provided with resistance R3 and electric capacity C4 in described filter circuit, the of resistance R3
One end is connected with the base stage of audion Q2, second end of electric capacity R3 respectively with first end of electric capacity C4 and exchanging of rectification circuit
Input is connected, and second end of electric capacity C4 fixes end phase with the ac input end of rectification circuit and the second of potentiometer W1 respectively
Connecting, preferred resistance R3 uses 5.1K Chip-R, and electric capacity C4 uses 100 μ F/15V electrochemical capacitors, and the positive pole of electric capacity C4
End is connected with second end of resistance R3.
Embodiment 6:
The present embodiment is to optimize further on the basis of any of the above-described embodiment, the most to better implement the present invention,
As it is shown in figure 1, use following set-up mode especially: be provided with diode D3, diode D4, diode D5 in described rectification circuit
And the positive pole of diode D6, diode D3 and diode D6 is connected and is connected with second end of resistance R3, diode D4's
Negative pole is connected with the negative pole of diode D5 and is connected with second end of electric capacity C4, and the negative pole of diode D3 is with diode D4's
Positive pole is connected and fixes end with the second of potentiometer W2 and is connected, and the positive pole of diode D5 is connected with the negative pole of diode D6
And fix end with the first of potentiometer W2 and be connected.
Embodiment 7:
The present embodiment is to optimize further on the basis of any of the above-described embodiment, the most to better implement the present invention,
As it is shown in figure 1, use following set-up mode especially: described diode D3, diode D4, diode D5 and diode D6 all use
IN4004 diode.
Embodiment 8:
The present embodiment is to optimize further on the basis of any of the above-described embodiment, the most to better implement the present invention,
As it is shown in figure 1, use following set-up mode especially: described resistance R1 uses the Chip-R of 500K, and described electric capacity C1 uses
The patch capacitor of 0.22 μ F, described electric capacity C3 uses the electrochemical capacitor of 100 μ F/50V, and the positive pole of electric capacity C3 is with diode D1's
Negative pole is connected, and described diode D1 uses IN4007 diode.
Embodiment 9:
The present embodiment is to optimize further on the basis of any of the above-described embodiment, the most to better implement the present invention,
As it is shown in figure 1, use following set-up mode especially: described electric capacity C2 uses the electrochemical capacitor of 47 μ F/50V, and electric capacity C2 is just
Pole is connected with the negative pole of diode D1, and described diode D2 uses 2CP12 diode.
Embodiment 10:
The present embodiment is to optimize further on the basis of any of the above-described embodiment, the most to better implement the present invention,
As it is shown in figure 1, use following set-up mode especially: described resistance R2 uses 24K Chip-R, and described audion Q2 uses 3DG6
Audion, described audion Q1 uses 3DG130 audion, and described potentiometer W1 uses 200 ohm of potentiometers.
The above, be only presently preferred embodiments of the present invention, and the present invention not does any pro forma restriction, every depends on
Any simple modification of being made above example according to the technical spirit of the present invention, equivalent variations, each fall within the protection of the present invention
Within the scope of.
Claims (10)
1. one kind for carrying out the protection circuit of current transformer function and protecting, it is characterised in that: be provided with ac input circuit,
Relay circuit, switching tube circuit, filter circuit, rectification circuit and protection coil circuit, described ac input circuit and relay
Device circuit is connected, and described relay circuit is connected with switching tube circuit, and described switching tube circuit connects filter circuit, described
Filter circuit connects rectification circuit, and described rectification circuit connects protection coil circuit, and described relay circuit controls to connect to be protected
The catalyst of protection circuit；In described protection coil circuit, it is provided with potentiometer W2, control coil L1 and controls switch KT, described
First end of control coil L1 is fixed end be connected with first end of control switch KT and the first of potentiometer W2 respectively, described electricity
Second fixing end of position device is connected with second end of control switch KT and second end of control coil L1 respectively, described potentiometer
The fixing end of the first of W2 and second is fixed end and is all connected on the DC output end of rectification circuit.
A kind of protection circuit for carrying out current transformer function and protecting the most according to claim 1, it is characterised in that:
Described ac input circuit is provided with resistance R1, electric capacity C1, electric capacity C3 and diode D1, first end of described electric capacity C1 with
First end of resistance R1 is connected and is connected with alternating current power supply, and second end of described electric capacity C1 is connected with second end of resistance R1
Connecing and be connected with the positive pole of diode D1, the negative pole of diode D1 is connected and and relay circuit with first end of electric capacity C3
Being connected, second end of described electric capacity C3 is connected with alternating current power supply and switching tube circuit respectively.
A kind of protection circuit for carrying out current transformer function and protecting the most according to claim 2, it is characterised in that:
In described relay circuit, be provided with electric capacity C2, relay K A and diode D2, the first end of described relay K A respectively with
First end of electric capacity C2, the negative pole of diode D1, the negative pole of diode D2 and switching tube circuit are connected；Described relay K A
Second end connects second end of electric capacity C2, the positive pole of diode D2 and switching tube circuit respectively and is connected, and described relay K A is controlled
System connects control switch KT.
A kind of protection circuit for carrying out current transformer function and protecting the most according to claim 3, it is characterised in that:
Resistance R2, audion Q2, audion Q1 and potentiometer W1, first end of resistance R2 and two it are provided with in described switching tube circuit
The negative pole of pole pipe D2 is connected, and second end of resistance R2 is connected with the colelctor electrode of audion Q2, the base stage of audion Q2 and filter
Wave circuit is connected, and the emitter stage of audion Q2 is connected with the base stage of audion Q1, the colelctor electrode of audion Q1 and diode
The positive pole of D2 is connected, and the emitter stage of audion Q1 is fixed end with the first of potentiometer W1 and is connected, and the second of potentiometer W1 is solid
Fixed end is connected with the second end and the filter circuit of electric capacity C3 respectively.
A kind of protection circuit for carrying out current transformer function and protecting the most according to claim 4, it is characterised in that:
Being provided with resistance R3 and electric capacity C4 in described filter circuit, first end of resistance R3 is connected with the base stage of audion Q2, electric capacity
Second end of R3 is connected with first end of electric capacity C4 and the ac input end of rectification circuit respectively, and second end of electric capacity C4 is respectively
Fix end be connected with the ac input end of rectification circuit and the second of potentiometer W1.
A kind of protection circuit for carrying out current transformer function and protecting the most according to claim 5, it is characterised in that:
Diode D3, diode D4, diode D5 and diode D6, diode D3 and diode D6 it is provided with in described rectification circuit
Positive pole is connected and is connected with second end of resistance R3, the negative pole of diode D4 be connected with the negative pole of diode D5 and with electricity
The second end holding C4 is connected, and the negative pole of diode D3 is connected with the positive pole of diode D4 and fixes with the second of potentiometer W2
End is connected, and the positive pole of diode D5 is connected with the negative pole of diode D6 and fixes end with the first of potentiometer W2 and is connected.
A kind of protection circuit for carrying out current transformer function and protecting the most according to claim 6, it is characterised in that:
Described diode D3, diode D4, diode D5 and diode D6 all use IN4004 diode.
8. according to a kind of protection circuit for carrying out current transformer function and protecting described in any one of claim 2-7, its
It is characterised by: described resistance R1 uses the Chip-R of 500K, and described electric capacity C1 uses the patch capacitor of 0.22 μ F, described electric capacity
C3 uses the electrochemical capacitor of 100 μ F, and the positive pole of electric capacity C3 is connected with the negative pole of diode D1, and described diode D1 uses
IN4007 diode.
9. according to a kind of protection circuit for carrying out current transformer function and protecting described in any one of claim 3-7, its
It is characterised by: described electric capacity C2 uses the electrochemical capacitor of 47 μ F, and the positive pole of electric capacity C2 is connected with the negative pole of diode D1, institute
State diode D2 and use 2CP12 diode.
10. according to a kind of protection circuit for carrying out current transformer function and protecting described in any one of claim 4-7, its
Being characterised by: described resistance R2 uses 24K Chip-R, described audion Q2 uses 3DG6 audion, and described audion Q1 adopts
Using 3DG130 audion, described potentiometer W1 uses 200 ohm of potentiometers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610690920.XA CN106159900A (en) | 2016-08-20 | 2016-08-20 | A kind of protection circuit for carrying out current transformer function and protecting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610690920.XA CN106159900A (en) | 2016-08-20 | 2016-08-20 | A kind of protection circuit for carrying out current transformer function and protecting |
Publications (1)
| Publication Number | Publication Date |
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| CN106159900A true CN106159900A (en) | 2016-11-23 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610690920.XA Pending CN106159900A (en) | 2016-08-20 | 2016-08-20 | A kind of protection circuit for carrying out current transformer function and protecting |
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| CN (1) | CN106159900A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2062911U (en) * | 1989-09-18 | 1990-09-26 | 翁德光 | Fireproof alarm controller for tri-phase low-voltage power |
| CN201032683Y (en) * | 2007-01-09 | 2008-03-05 | 高子泉 | Overcurrent protection circuit |
| CN204720700U (en) * | 2015-06-14 | 2015-10-21 | 南安市德华电子设备厂 | A kind of overload protection alarm socket |
| CN205489446U (en) * | 2016-01-19 | 2016-08-17 | 深圳市骊微电子科技有限公司 | Intelligence supply control circuit |
-
2016
- 2016-08-20 CN CN201610690920.XA patent/CN106159900A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2062911U (en) * | 1989-09-18 | 1990-09-26 | 翁德光 | Fireproof alarm controller for tri-phase low-voltage power |
| CN201032683Y (en) * | 2007-01-09 | 2008-03-05 | 高子泉 | Overcurrent protection circuit |
| CN204720700U (en) * | 2015-06-14 | 2015-10-21 | 南安市德华电子设备厂 | A kind of overload protection alarm socket |
| CN205489446U (en) * | 2016-01-19 | 2016-08-17 | 深圳市骊微电子科技有限公司 | Intelligence supply control circuit |
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Application publication date: 20161123 |
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