CN201360132Y - Automatic action or warning circuit for wire breakage of circumscribed residual current mutual inductor - Google Patents
Automatic action or warning circuit for wire breakage of circumscribed residual current mutual inductor Download PDFInfo
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- CN201360132Y CN201360132Y CNU2009200381968U CN200920038196U CN201360132Y CN 201360132 Y CN201360132 Y CN 201360132Y CN U2009200381968 U CNU2009200381968 U CN U2009200381968U CN 200920038196 U CN200920038196 U CN 200920038196U CN 201360132 Y CN201360132 Y CN 201360132Y
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Abstract
The utility model provides an automatic action or warning circuit for wire breakage of a circumscribed residual current mutual inductor, which comprises a control unit, a first comparator unit, a first comparative voltage acquisition unit and a sampling voltage acquisition unit. The automatic action or warning circuit for wire breakage of the circumscribed residual current mutual inductor is arranged in a residual current protective device of the circumscribed residual current mutual inductor, and the wire breakage of a secondary circuit can be found in time, therefore, the secondary circuit coil of the residual current mutual inductor can automatically act or warn for indicating the wire breakage of the mutual inductor in case of break switches and in failure, and the residual current protective device has the essential protective effect and avoids the generation of major potential safety hazards. The automatic action or warning circuit is additionally provided with an anti-jamming unit, and the utility model can convert real-time signal detection into integrated signal detection of the wire breakage detection of the residual current mutual inductor, so that the detection result meets the automatic action or warning requirements in the wire breakage process of the residual current mutual inductor within several seconds and reduces the phenomenon of false operation.
Description
Technical field
The utility model relates to a kind of disconnection auto-action or warning circuit, relates in particular to a kind of Aftercurrent protecting equipment external residual current transformer secondary break auto-action or warning circuit.
Background technology
Aftercurrent protecting equipment is to be used for electric wiring is carried out earth fault protection, prevents equipment and electrical fire accident that earth fault current causes, and also can be used to provides the indirect contact protection to personal Danger Electric shock risk.Because Aftercurrent protecting equipment moves in electrical network for a long time; for the external residual current transformer that is installed separately; its residual current transformer and lead-in wire be because of in the housing that installs, and be vulnerable to the destruction of the erosion of effect, weather of external force and worm mouse and break.If secondary circuit coil breakage and can not find in time that Aftercurrent protecting equipment will lose protective effect will bring major safety risks.
And at present, the function of auto-action or warning when in the product that residual current transformer and control section are installed separately, corresponding residual current transformer secondary circuit coil breakage or fault not being set.
The utility model content
The technical problem that the utility model solved provides a kind of external residual current transformer disconnection auto-action or warning circuit; make the output signal of testing circuit can reflect true broken string situation, thereby make control unit Aftercurrent protecting equipment auto-action or warning when external residual current transformer secondary circuit coil breakage or fault.
The technical solution of the utility model is: a kind of external residual current transformer disconnection auto-action or warning circuit is characterized in that comprising:
First comparative voltage obtains the unit, is used to obtain the first comparative voltage V1, and this first comparative voltage V1 outputs to the comparative voltage input of first comparator unit;
Sampling voltage obtains the unit, is used to obtain the residual current transformer secondary break and differentiates sampling voltage; This sampling voltage is input to the sampling voltage input of first comparator unit;
First comparator unit realizes the comparison to first comparative voltage, sampling voltage, and comparative result is exported as the burn out detection signal;
Control unit is used to receive the burn out detection signal, and according to testing result control action or warning circuit.
Wherein control unit comprises: resistance R 9, resistance R 11, resistance R 12, capacitor C 2, diode D1, triode G1, triode G2, relay K.Described resistance R 9 one termination powers+5V, another termination capacitor C 2, resistance R 11, its tie point is the input of the control signal of control unit, resistance R 11 another termination triode G1 base stages, capacitor C 2 another termination power ground.Resistance R 12 1 termination powers+5V, the other end and triode G1 collector electrode and triode G2 base stage link together.Triode G1, G2 emitter connect power supply ground.One termination power of diode D1 negative pole and relay K+5V, the linking together of the other end of relay K with triode G2 collector electrode, diode D1 positive pole.Relay K a pair of often opened, normally closed interlock is the output of control signal.
First comparator unit comprises an operational amplifier; The in-phase input end U of described operational amplifier
A-3The common tie point of connecting resistance R3,4 liang of resistance of resistance R, reverse input end U
A-2The common tie point of connecting resistance R1,2 liang of resistance of resistance R, output U
A-1An end that connects resistance R 8.The power end U of this integrated circuit Ua
A-8Connection+5V power supply, earth terminal U
A-4Connect power supply ground.
First comparative voltage obtains the unit, comprises the resistance R 1, the resistance R 2 that are series between positive source and the power supply ground, and obtains the described first comparative voltage V1 from the intermediate node of two resistance.
Sampling voltage obtains the unit, comprises sample resistance R10, divider resistance R3, divider resistance R4; Described sample resistance R10 one termination power+5V, another termination external residual current transformer secondary coil one end, the voltage that its tie point obtains is connected to power supply ground through resistance R 3, the resistance R 4 of series connection; Another termination power ground of residual current transformer secondary coil, the intermediate node voltage of described resistance R 3, resistance R 4 is as sampling voltage.Be used to obtain residual current transformer secondary coil broken string and differentiate sampling voltage; This sampling voltage is input to the sampling voltage input of first comparator unit;
As further improvement of the utility model, between first comparing unit and control unit, also comprise an anti-interference unit, in this anti-interference unit, comprise following three parts:
Second comparative voltage obtains the unit, is used to obtain the second comparative voltage V2, and outputs to the comparative voltage input of second comparator unit;
Integral unit is used to receive the output end voltage of first comparator unit, obtains the voltage signal Vj through integration, and this voltage is input to the input of second comparator unit;
Second comparator unit realizes the comparison to the second comparative voltage V2 of described integral unit output voltage and described second comparative voltage acquisition unit; And comparative result exported as the burn out detection signal.
Second comparative voltage in the anti-interference unit obtains the unit, comprises the resistance R 6, the resistance R 7 that are connected between positive source and the power supply ground; The intermediate node voltage of two resistance is as the second comparative voltage V2.
Integral unit in the anti-interference unit comprises resistance R 5, resistance R 8, capacitor C 1; Described resistance R 5 one ends connect positive source, capacitor C 1 one termination power ground, resistance R 8 one ends connect the output of first comparator unit, and the common junction voltage of resistance R 8 other ends and resistance R 5, capacitor C 1 is connected to the input of second comparator unit as integral voltage.
Second comparator unit in the anti-interference unit comprises an operational amplifier; The in-phase input end U of described operational amplifier
A-5Connecting resistance R5, resistance R 8, capacitor C 1 three-element common tie point, reverse input end U
A-6The common tie point of connecting resistance R6,7 liang of resistance of resistance R, output U
A-7Connect resistance R 9, resistance R 11, capacitor C 2 three-element common tie points.
The comparative voltage input of first comparator unit is the inverting input of comparator unit; The sampling voltage input of described first comparator unit is the in-phase input end of comparator unit; The comparative voltage input of described second comparator is the inverting input of comparator unit; The integrated signal input of described second comparator is the in-phase input end of comparator unit.
In the Aftercurrent protecting equipment product of external residual current transformer; be provided with residual current transformer disconnection auto-action of the present utility model or warning circuit; can in time find the secondary circuit coil breakage; make residual current transformer secondary circuit coil the device auto-action or the indication transformer disconnection of reporting to the police when broken string or fault; Aftercurrent protecting equipment will play the protective effect of essence, avoid the generation of major safety risks.
Simultaneously, (comprise: second comparative voltage obtains the unit to have increased anti-interference unit, second comparator unit, integral unit,) this anti-interference unit can change external residual current transformer secondary coil burn out detection into the detection of integrated signal from the detection of real-time signal, have only the stable disconnection signal of time several seconds to exist, just make control unit carry out action.Make testing result satisfy the time requirement of residual current transformer disconnection auto-action or warning, reduced wrong report malfunction phenomenon again.
Description of drawings
Fig. 1 is a schematic diagram of the present utility model.
Fig. 2 is a circuit diagram of the present utility model.
Fig. 3 is the schematic diagram of the utility model preferred version.
Fig. 4 is the circuit diagram of the utility model preferred version.
Embodiment
Fig. 2 is the circuit diagram of external residual current transformer disconnection auto-action or warning circuit.Specifically be applied in the external residual current transformer disconnection auto-action or warning circuit of Aftercurrent protecting equipment.
As shown in the figure, this disconnection protection circuit comprises integrated circuit Ua, resistance R 1, resistance R 2, resistance R 3, resistance R 4, resistance R 9, resistance R 10, resistance R 11, resistance R 12, capacitor C 2, diode D1, triode G1, triode G2, relay K.
The positive source of this testing circuit is+the 5V power supply among the figure.
Integrated circuit Ua is the integrated circuit with comparator of two open circuit outputs among Fig. 2, and this disconnection protection circuit uses first comparator wherein to form first comparator unit.The power end U of this integrated circuit Ua
A-8Connection+5V power supply, the earth terminal U of this integrated circuit Ua
A-4Connect power supply ground.
Resistance R 10, resistance R 3, resistance R 4 are formed sampling voltage acquisition unit among Fig. 2.Resistance R 10 1 terminations+5V power supply wherein, another termination residual current transformer secondary coil of resistance R 10, another termination power ground of residual current transformer secondary coil, resistance R 10 obtains detecting voltage with the common junction of residual current transformer secondary coil.The resistance R 3 of this detection voltage by being in series, resistance R 4 is connected to power supply ground, and in resistance R 3, the intermediate node of resistance R 4 forms sampling voltage.This sampling voltage outputs to the first comparator unit in-phase input end U
A-3
Control unit comprises among Fig. 2: resistance R 9, resistance R 11, resistance R 12, capacitor C 2, diode D1, triode G1, triode G2, relay K.Described resistance R 9 one termination powers+5V, another termination capacitor C 2, resistance R 11, its tie point is the input of the control signal of control unit, resistance R 11 another termination triode G1 base stages, capacitor C 2 another termination power ground.Resistance R 12 1 termination powers+5V, the other end and triode G1 collector electrode and triode G2 base stage link together.Triode G1, G2 emitter connect power supply ground.One termination power of diode D1 negative pole and relay K+5V, the linking together of the other end of relay K with triode G2 collector electrode, diode D1 positive pole.Relay K a pair of often opened, normally closed interlock is the output of control signal.
The normal phase input end U of first comparator
A-3Inverting input U with first comparator
A-2Relatively, can obtain different output.If normal phase input end U
A-3Less than inverting input U
A-2, U then
A-1Output low level illustrates that sampling voltage is low than the first comparative voltage V1, and just the residual current transformer secondary coil of external residual current protective device is in operate as normal.If normal phase input end U
A-3Greater than inverting input U
A-2, U then
A-1The output high level illustrates sampling voltage than the first comparative voltage V1 height, and just the residual current transformer secondary coil of external residual current protective device is undesired.After control unit receives high level signal; this current potential is delivered to the G1 base stage through R11; make the G1 conducting; the G1 collector potential descends, and the G2 base potential descends, and G2 ends; make sensitive relay K coil losing electricity; the normally opened contact of K is opened, and the Aftercurrent protecting equipment action realizes auto-action or warning function.This control unit can also can be the control device of single-chip microcomputer or other type as shown.
But because the first comparator output terminal U is depended in the judgement of this circuit broken string
A-1Voltage, and this output U
A-1Voltage is a real-time signal, the instantaneous value of first comparative voltage V1 of input and sampling voltage is relevant during only with sampling, with instantaneous value as foundation, though can improve the speed of differentiation, but very easily be subjected to instantaneous nanosecond, the interference of Millisecond, the malfunction wrong report takes place.Therefore,, between first comparing unit and control unit, also comprise an anti-interference unit, comprise that second comparator unit, second comparative voltage obtain unit, integral unit as a kind of preferred version of the present utility model.Though because just can realize external residual current transformer disconnection auto-action or warning function by the combination of sampling voltage acquisition unit, first comparator unit, first comparative voltage acquisition unit, control unit.But can produce misoperation when occurring for instantaneous interference signal.Increasing anti-interference unit can increase the reliability of circuit, reduces the probability of misoperation.
Second comparator unit is used for the integral voltage of integral unit output and second comparative voltage of second comparative voltage acquisition unit output and compares, and comparative result is outputed to control unit as the burn out detection signal.
Resistance R 8, resistance R 5, capacitor C 1 are formed integral unit among Fig. 4.This integral unit with capacitor C 1 as integral element, with the output U of first comparator unit
A-1Control capacitance C1 discharges and recharges.Concrete connected mode is: resistance R 5 and capacitor C 1 are series between positive source and the power supply ground, and resistance R 5 one ends connection power supply+5V, and capacitor C 1 one ends connect power supply ground, and the intermediate node of resistance R 5, capacitor C 1 connects the second comparator unit normal phase input end U
A-5The first comparator unit output U of integrated circuit Ua
A-1Connect resistance R 8, the other end of resistance R 8 is to the in-phase input end U of this integrated circuit second comparator
A-5On resistance R 5 and capacitor C 1 common junction.
Resistance R 6, resistance R 7 are formed second comparative voltage acquisition unit among Fig. 4.Described resistance R 6, resistance R 7 are connected between power supply+5V and the power supply ground, obtain the second comparative voltage V2 on the intermediate node of two resistance, and this second comparative voltage V2 offers the second comparator unit inverting input U
A-6By changing the resistance of resistance R 6, resistance R 7, can obtain required magnitude of voltage as the second comparative voltage V2.
Resistance R 9 is connected power supply+5V and the described second comparator output terminal U among Fig. 4
A-7Between, itself and the second comparator output terminal U
A-7With an end common junction of capacitor C 2 be the input of control unit, the second comparator output terminal U
A-7Output signal (high level or low level) output to control unit by this node.
The operation principle that second comparator unit, second comparative voltage obtain the unit is identical with the operation principle that first comparator unit, first comparative voltage obtain the unit.
Integral unit discharge and recharge the control that is subjected to the described first comparator unit output signal, when first comparator unit output high level,, obtain the integral voltage Vj of high level through time several seconds, and voltage Vj is greater than voltage V2 to this integral unit charging; When the first comparing unit output low level, to this integral unit discharge, the integral voltage Vj that makes this integral unit is less than voltage V2.
The first comparator output terminal U
A-1During high level to integral unit capacitor C 1 charging undertaken by R8, make charging process slower the parameter setting of resistance R 8, the time is longer.Therefore, when occurring for instantaneous interference signal, the first comparator output terminal U
A-1When instantaneous interference high level occurring, the integral voltage Vj at the two ends of capacitor C 1 can not raise at once and surpass second comparative voltage.Even be subjected to the interference of the broken string illusion of short time, capacitor C 1 current potential rises still needs time several seconds, before this current potential rises, and the second comparator output terminal U
A-7All the time output low level does not produce the malfunction false positive signal.Therefore under the situation of selecting suitable parameter, can guarantee the antijamming capability of circuit, the situation that will break accurately reflects.
When the situation that will break takes place really, the first comparator unit output U
A-1During long-time high level, the first comparator unit output U
A-1High level directly charges the second comparator unit in-phase input end U by R8 to capacitor C 1
A-5Input high level surpasses second comparative voltage, the second comparator unit output U
A-7The output high level, after control unit receives this high level signal, control Aftercurrent protecting equipment auto-action or warning.
Promptly when the external residual current transformer secondary coil does not break, the common junction current potential that resistance R 10 is connected with the external residual current transformer secondary coil is pulled low to electronegative potential by the external residual current transformer secondary coil, the U of input in the same way of first comparator unit
A-3Current potential is lower than the reverse input end U of first comparator unit
A-2Current potential, the output U of first comparator unit
A-1Output low level, this low level is equivalent to power supply ground.At this moment, this low level makes capacitor C 1 discharge by resistance R 8, and the voltage of capacitor C 1 is released, and makes voltage Vj (the second comparator in-phase end U just
A-5Voltage) be lower than the second comparator reverse input end U
A-6The second comparative voltage V2, therefore, the second comparator output terminal U
A-7Output low level, this low level outputs to the control circuit input, and control unit is failure to actuate.
When the external residual current transformer secondary coil breaks, because of opening circuit of external residual current transformer secondary coil, the common junction current potential that resistance R 10 is connected with the external residual current transformer secondary coil is drawn high to power supply+5V current potential, after resistance R 3, resistance R 4 dividing potential drops, the in-phase input end U of first comparator unit
A-3Current potential is higher than the inverting input U of first comparator unit
A-2Current potential, the output U of first comparator
A-1The output high level at this moment, to capacitor C 1 charging, raises capacitor C 1 both end voltage Vj during by resistance R 8, and this voltage Vj is input to the second comparator in-phase input end U as integral voltage
A-5, its magnitude of voltage finally is higher than the second comparator reverse input end U
A-6The second comparative voltage V2, therefore, the second comparator output terminal U
A-7The output high level.External residual current transformer secondary coil broken string is described, after control unit receives this high level signal, control Aftercurrent protecting equipment auto-action or warning circuit.
The foregoing description has only illustrated two kinds of execution modes of the present utility model, and in fact the utility model can also have the form of other variation.For example, the voltage of the connection of the positive end of oppisite phase of comparator can be opposite with the connected mode of present embodiment; Sampling unit, integral unit can adopt other form.
The above only is a preferred implementation of the present utility model; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the utility model principle; can also make some improvements and modifications, these improvements and modifications also should be considered as protection range of the present utility model.
Claims (10)
1, a kind of external residual current transformer disconnection auto-action or warning circuit is characterized in that comprising:
First comparative voltage obtains the unit, is used to obtain first comparative voltage (V1), and this first comparative voltage (V1) outputs to the comparative voltage input of first comparator unit;
Sampling voltage obtains the unit, is used to obtain the residual current transformer secondary break and differentiates sampling voltage; This sampling voltage is input to the sampling voltage input of first comparator unit;
First comparator unit realizes the comparison to first comparative voltage, sampling voltage, and comparative result is exported as the burn out detection signal;
Control unit is used to receive the burn out detection signal, and according to testing result control action or warning circuit.
2, external residual current transformer disconnection auto-action according to claim 1 or warning circuit is characterized in that: described control unit comprises resistance (R9), resistance (R11), resistance (R12), electric capacity (C2), diode (D1), triode (G1), triode (G2), relay (K); Described resistance (R9) one termination power+5V, another termination capacitor (C2), resistance (R11), its tie point is the input of the control signal of control unit, another termination triode (G1) base stage of resistance (R11), another termination power ground of electric capacity (C2); Resistance (R12) one termination power+5V, the other end and triode (G1) collector electrode and triode (G2) base stage link together; Triode (G1, G2) emitter connects power supply ground; One termination power+the 5V of diode (D1) negative pole and relay (K), the other end of relay (K) and triode (G2) collector electrode, diode (D1) positive pole link together; Relay (K) a pair of often leaves, normally closed interlock is the output of control signal.
3, external residual current transformer disconnection auto-action according to claim 1 or warning circuit is characterized in that: described first comparator unit comprises an operational amplifier; In-phase input end (the U of described operational amplifier
A-3) the common tie point of connecting resistance (R3), resistance (R4) two resistance, reverse input end (U
A-2) the common tie point of connecting resistance (R1), resistance (R2) two resistance, output (U
A-1) connect an end of resistance (R8); Power end (the U of this integrated circuit (Ua)
A-8) connection+5V power supply, earth terminal (U
A-4) connection power supply ground.
4, external residual current transformer disconnection auto-action according to claim 1 or warning circuit, it is characterized in that: described first comparative voltage obtains the unit and comprises resistance (R1), the resistance (R2) that is series between positive source and the power supply ground, and obtains described first comparative voltage (V1) from the intermediate node of two resistance.
5, external residual current transformer disconnection auto-action according to claim 1 or warning circuit is characterized in that: described sampling voltage obtains the unit and comprises sample resistance (R10), divider resistance (R3), divider resistance (R4); Described sample resistance (R10) one termination power+5V, another termination external residual current transformer secondary coil one end, the voltage that its tie point obtains is connected to power supply ground through resistance (R3), the resistance (R4) of series connection; Another termination power ground of residual current transformer secondary coil, the intermediate node voltage of described resistance (R3), resistance (R4) is as sampling voltage; Be used to obtain residual current transformer secondary coil broken string and differentiate sampling voltage; This sampling voltage is input to the sampling voltage input of first comparator unit.
6, external residual current transformer disconnection auto-action according to claim 1 or warning circuit, it is characterized in that: between described first comparing unit and control unit, also comprise an anti-interference unit, in this anti-interference unit, comprise following three parts:
Second comparative voltage obtains the unit, is used to obtain second comparative voltage (V2), and outputs to the comparative voltage input of second comparator unit;
Integral unit is used to receive the output end voltage of first comparator unit, obtains the voltage signal (Vj) through integration, and this voltage is input to the input of second comparator unit;
Second comparator unit realizes the comparison to second comparative voltage (V2) of described integral unit output voltage and described second comparative voltage acquisition unit; And comparative result exported as the burn out detection signal.
7, external residual current transformer disconnection auto-action according to claim 6 or warning circuit is characterized in that: second comparative voltage acquisition unit comprises resistance (R6), the resistance (R7) that is connected between positive source and the power supply ground in the described anti-interference unit; The intermediate node voltage of two resistance is as second comparative voltage (V2).
8, external residual current transformer disconnection auto-action according to claim 6 or warning circuit is characterized in that: integral unit comprises resistance (R5), resistance (R8), electric capacity (C1) in the described anti-interference unit; Described resistance (R5) end connects positive source, electric capacity (C1) termination power ground, resistance (R8) end connects the output of first comparator unit, the common junction voltage of resistance (R8) other end and resistance (R5), electric capacity (C1) is connected to the input of second comparator unit as integral voltage.
9, external residual current transformer disconnection auto-action according to claim 6 or warning circuit is characterized in that: second comparator unit comprises an operational amplifier in the described anti-interference unit; In-phase input end (the U of described operational amplifier
A-5) connecting resistance (R5), resistance (R8), the three-element common tie point of electric capacity (C1), reverse input end (U
A-6) the common tie point of connecting resistance (R6), resistance (R7) two resistance, output (U
A-7) connect resistance (R9), resistance (R11), the three-element common tie point of electric capacity (C2).
10, external residual current transformer disconnection auto-action according to claim 6 or warning circuit is characterized in that: the comparative voltage input of described first comparator unit is the inverting input of comparator unit; The sampling voltage input of described first comparator unit is the in-phase input end of comparator unit; The comparative voltage input of described second comparator is the inverting input of comparator unit; The integrated signal input of described second comparator is the in-phase input end of comparator unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2009200381968U CN201360132Y (en) | 2009-01-20 | 2009-01-20 | Automatic action or warning circuit for wire breakage of circumscribed residual current mutual inductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2009200381968U CN201360132Y (en) | 2009-01-20 | 2009-01-20 | Automatic action or warning circuit for wire breakage of circumscribed residual current mutual inductor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201360132Y true CN201360132Y (en) | 2009-12-09 |
Family
ID=41425897
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2009200381968U Expired - Lifetime CN201360132Y (en) | 2009-01-20 | 2009-01-20 | Automatic action or warning circuit for wire breakage of circumscribed residual current mutual inductor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201360132Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101557094B (en) * | 2009-01-20 | 2011-04-20 | 南京鼎牌电器有限公司 | Disconnection auto-action or alarm circuit of external residual current transformer |
-
2009
- 2009-01-20 CN CNU2009200381968U patent/CN201360132Y/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101557094B (en) * | 2009-01-20 | 2011-04-20 | 南京鼎牌电器有限公司 | Disconnection auto-action or alarm circuit of external residual current transformer |
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| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20091209 Effective date of abandoning: 20090120 |