阅读说明：本技术 断路器电校验质量判定方法 (circuit breaker electric checking quality judgment method ) 是由 康宽 罗涛 彭勃 于 2019-08-15 设计创作，主要内容包括：一种断路器电校验质量判定方法,其包括以下步骤：S1：获得合格断路器的时间-最小安全电学特性曲线和时间-最大安全电学特性曲线；S2：获得待测断路器的时间-电学特性曲线；S3：将待测断路器的时间-电学特性曲线分别与时间-最大安全电学特性曲线和时间-最小安全电学特性曲线对比；通过将待测断路器的时间-电学特性曲线与合格断路器的时间-电学特性曲线进行对比分析,能够快速、准确地检测出断路器产品的瑕疵,防止瑕疵断路器在生产过程中被当成合格品流出。(A method for judging the quality of electric check of a circuit breaker comprises the following steps: s1: obtaining a time-minimum safety electrical characteristic curve and a time-maximum safety electrical characteristic curve of the qualified circuit breaker; s2: obtaining a time-electrical characteristic curve of the circuit breaker to be tested; s3: comparing the time-electrical characteristic curve of the circuit breaker to be tested with the time-maximum safety electrical characteristic curve and the time-minimum safety electrical characteristic curve respectively; by comparing and analyzing the time-electrical characteristic curve of the circuit breaker to be detected and the time-electrical characteristic curve of the qualified circuit breaker, the defects of the circuit breaker product can be quickly and accurately detected, and the defective circuit breaker is prevented from flowing out as a qualified product in the production process.)

1. A method for judging the quality of electric check of a circuit breaker is characterized by comprising the following steps: the method comprises the following steps:

S1: obtaining a time-minimum safety electrical characteristic curve and a time-maximum safety electrical characteristic curve of the qualified circuit breaker;

s2: obtaining a time-electrical characteristic curve of the circuit breaker to be tested;

s3: comparing the time-electrical characteristic curve of the circuit breaker to be tested with the time-maximum safety electrical characteristic curve and the time-minimum safety electrical characteristic curve respectively;

the method comprises the steps that an electrical characteristic value of any time point on a time-electrical characteristic curve of a circuit breaker to be tested is taken and is respectively compared with an electrical characteristic value of a time-maximum safe electrical characteristic curve and an electrical characteristic value of a time-minimum safe electrical characteristic curve at the time point;

And if the electrical characteristic values of the time-electrical characteristic curve of the circuit breaker to be tested are smaller than the electrical characteristic value of the time-maximum safe electrical characteristic curve and larger than the electrical characteristic value of the time-minimum safe electrical characteristic curve at the time point, the circuit breaker to be tested is a qualified product.

2. The method of determining the quality of an electrical check of a circuit breaker of claim 1, wherein: step S4, taking the electrical characteristic value of any time point on the time-electrical characteristic curve of the circuit breaker to be tested, and comparing the electrical characteristic value with the electrical characteristic value of the time-maximum safe electrical characteristic curve and the electrical characteristic value of the time-minimum safe electrical characteristic curve at the time point respectively;

If the electrical characteristic values of the time-electrical characteristic curves of the circuit breaker to be tested are all larger than the electrical characteristic value of the time-maximum safe electrical characteristic curve at the time point, the circuit breaker to be tested is a first-class fault;

And if the electrical characteristic values of the time-electrical characteristic curves of the circuit breaker to be tested are smaller than the electrical characteristic value of the time-minimum safety electrical characteristic curve at the time point, the circuit breaker to be tested is a second type of fault.

3. the method of determining the quality of an electrical check of a circuit breaker of claim 1, wherein: the method further comprises the step S5 of obtaining the intersection point of the time-electrical characteristic curve of the circuit breaker to be tested and the time-maximum safety electrical characteristic curve of the standard circuit breaker if the intersection point exists between the time-electrical characteristic curve of the circuit breaker to be tested and the time-maximum safety electrical characteristic curve, obtaining the slope of the time-electrical characteristic curve of the circuit breaker to be tested at the time point, and comparing the slope with the slope of the time-maximum safety electrical characteristic curve of the standard circuit breaker at the time point;

If the slope of the time-electrical characteristic curve of the circuit breaker to be tested is greater than the slope of the time-maximum safe electrical characteristic curve at the time point, the circuit breaker to be tested is a third type of fault;

if the slope of the time-electrical characteristic curve of the circuit breaker to be tested is smaller than the slope of the time-maximum safe electrical characteristic curve at the time point, the fault is a fourth type of fault.

4. the method of determining the quality of an electrical check of a circuit breaker of claim 1, wherein: the method further comprises the step S6 of obtaining the intersection point of the time-electrical characteristic curve of the circuit breaker to be tested and the time-minimum safety electrical characteristic curve of the standard circuit breaker if the intersection point exists between the time-electrical characteristic curve of the circuit breaker to be tested and the time-minimum safety electrical characteristic curve, obtaining the slope of the time-electrical characteristic curve of the circuit breaker to be tested at the time point, and comparing the slope with the slope of the time-minimum safety electrical characteristic curve of the standard circuit breaker at the time point;

If the slope of the time-electrical characteristic curve of the circuit breaker to be tested is greater than the slope of the time-minimum safety electrical characteristic curve at the time point, the fault is a fifth type of fault;

And if the slope of the time-electrical characteristic curve of the circuit breaker to be tested is smaller than the slope of the time-minimum safety electrical characteristic curve at the time point, judging that the circuit breaker is a sixth fault.

5. the method for determining the quality of an electrical check of a circuit breaker according to any of claims 1 to 4, wherein: the time-electrical characteristic curve, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve in step S1 are all time-current characteristic curves, time-voltage characteristic curves, time-power characteristic curves or time-resistance characteristic curves.

6. The method of determining the quality of an electrical check of a circuit breaker of claim 1, wherein: the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve in the step S1 are obtained based on big data statistical analysis.

7. The method for determining the quality of an electrical check of a circuit breaker according to any of claims 1 to 4, wherein: the step S1 includes the steps of:

S11: detecting and obtaining time-electrical characteristic curves of a plurality of standard circuit breakers;

S12: respectively aiming at different times, taking the maximum value in the time-electrical characteristic curves of the plurality of standard circuit breakers to obtain the time-maximum safe electrical characteristic curve of the circuit breaker; or, the maximum value in the time-electrical characteristic curves of the plurality of standard circuit breakers is multiplied by the maximum value coefficient to obtain the time-maximum safe electrical characteristic curve of the circuit breaker;

S13: respectively aiming at different times, taking the minimum value in the time-electrical characteristic curves of the plurality of standard circuit breakers to obtain a time-minimum safety electrical characteristic curve; or the minimum value in the time-electrical characteristic curves of the plurality of standard circuit breakers is multiplied by the minimum value coefficient to obtain the time-minimum safety electrical characteristic curve.

8. the method of determining the quality of an electrical check of a circuit breaker of claim 7, wherein: and the following tracking step is also included, when the circuit breaker to be detected is judged to be unqualified, the circuit breaker to be detected is rechecked and detected, and if the circuit breaker to be detected is qualified after rechecking, the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve of the circuit breaker are corrected based on the time-electrical characteristic curve of the circuit breaker to be detected.

9. the method of determining the quality of an electrical check of a circuit breaker of claim 8, wherein: and for the products which are detected to be qualified and then are found to be fault products, the technical personnel analyze the reasons of the fault products, if the faults are caused by the reasons related to the detection of the circuit breaker electrical verification quality judgment method, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve of the circuit breaker are corrected based on the time-electrical characteristic curve of the fault products.

10. the method of determining the quality of an electrical check of a circuit breaker of claim 9, wherein: taking a corresponding fault electrical characteristic value on a time-electrical characteristic curve of a fault product, a maximum electrical characteristic value on a time-maximum safety electrical characteristic curve corresponding to a time point, and a minimum electrical characteristic value on a time-minimum safety electrical characteristic curve corresponding to the time point;

if the fault electrical characteristic value is smaller than the maximum electrical characteristic value and larger than the maximum electrical characteristic value multiplied by the maximum fault correction coefficient, and the maximum fault correction coefficient is smaller than 1, correcting the time-maximum safe electrical characteristic curve of the corresponding time point by using the fault electrical characteristic value;

and if the fault electrical characteristic value is larger than the minimum electrical characteristic value and smaller than the minimum electrical characteristic value multiplied by the minimum fault correction coefficient, and the minimum fault correction coefficient is larger than 1, correcting the time-minimum safety electrical characteristic curve corresponding to the time point by using the fault electrical characteristic value.

Technical Field

The invention relates to the field of low-voltage electric appliances, in particular to a method for judging the electric checking quality of a circuit breaker.

background

at present, various unqualified products such as burnt-out products, phase-lacking products and non-energized products are often found in the production and return of products of the circuit breakers and the residual current circuit breakers, and the reason is that the defective circuit breakers are taken as qualified products to flow out in the production process. These defects include: large contact resistance, poor spot welding, short circuit between the coil and the bimetal, error spot welding of the bimetal, wrong coil installation and the like. The conventional electric checking table does not have the capability of picking out the products, the conventional checking table can automatically adjust the current according to the resistance value of the circuit breaker, and the checking cannot be stopped even if the current is large, so that unqualified products are taken as qualified products to flow out. However, under the current technical conditions, the defects such as large contact resistance, error double-gold spot welding, poor spot welding, wrong coil installation, short circuit between the coil and the double-gold, and the like, are not completely eliminated due to lack of clear indexes, so that the quality of the circuit breaker is unstable.

disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a method for judging the electric checking quality of a circuit breaker accurately and quickly.

in order to achieve the purpose, the invention adopts the following technical scheme:

a method for judging the quality of electric check of a circuit breaker comprises the following steps:

s1: obtaining a time-minimum safety electrical characteristic curve and a time-maximum safety electrical characteristic curve of the qualified circuit breaker;

S2: obtaining a time-electrical characteristic curve of the circuit breaker to be tested;

s3: comparing the time-electrical characteristic curve of the circuit breaker to be tested with the time-maximum safety electrical characteristic curve and the time-minimum safety electrical characteristic curve respectively;

The method comprises the steps that an electrical characteristic value of any time point on a time-electrical characteristic curve of a circuit breaker to be tested is taken and is respectively compared with an electrical characteristic value of a time-maximum safe electrical characteristic curve and an electrical characteristic value of a time-minimum safe electrical characteristic curve at the time point;

And if the electrical characteristic values of the time-electrical characteristic curve of the circuit breaker to be tested are smaller than the electrical characteristic value of the time-maximum safe electrical characteristic curve and larger than the electrical characteristic value of the time-minimum safe electrical characteristic curve at the time point, the circuit breaker to be tested is a qualified product.

Preferably, the method further includes step S4, taking an electrical characteristic value of any time point on the time-electrical characteristic curve of the circuit breaker to be tested, and comparing the electrical characteristic value with the electrical characteristic value of the time-maximum safety electrical characteristic curve and the electrical characteristic value with the electrical characteristic value of the time-minimum safety electrical characteristic curve at the time point respectively;

If the electrical characteristic values of the time-electrical characteristic curves of the circuit breaker to be tested are all larger than the electrical characteristic value of the time-maximum safe electrical characteristic curve at the time point, the circuit breaker to be tested is a first-class fault;

and if the electrical characteristic values of the time-electrical characteristic curves of the circuit breaker to be tested are smaller than the electrical characteristic value of the time-minimum safety electrical characteristic curve at the time point, the circuit breaker to be tested is a second type of fault.

Preferably, the method further includes step S5, if there is an intersection point between the time-electrical characteristic curve of the circuit breaker to be tested and the time-maximum safety electrical characteristic curve, acquiring the intersection point between the time-electrical characteristic curve of the circuit breaker to be tested and the time-maximum safety electrical characteristic curve of the standard circuit breaker, acquiring a slope of the time-electrical characteristic curve of the circuit breaker to be tested at the time point, and comparing the slope with a slope of the time-maximum safety electrical characteristic curve of the standard circuit breaker at the time point;

If the slope of the time-electrical characteristic curve of the circuit breaker to be tested is greater than the slope of the time-maximum safe electrical characteristic curve at the time point, the circuit breaker to be tested is a third type of fault;

if the slope of the time-electrical characteristic curve of the circuit breaker to be tested is smaller than the slope of the time-maximum safe electrical characteristic curve at the time point, the fault is a fourth type of fault.

Preferably, the method further includes step S6, if there is an intersection point between the time-electrical characteristic curve of the circuit breaker to be tested and the time-minimum safety electrical characteristic curve, acquiring the intersection point between the time-electrical characteristic curve of the circuit breaker to be tested and the time-minimum safety electrical characteristic curve of the standard circuit breaker, acquiring a slope of the time-electrical characteristic curve of the circuit breaker to be tested at the time point, and comparing the slope with a slope of the time-minimum safety electrical characteristic curve of the standard circuit breaker at the time point;

if the slope of the time-electrical characteristic curve of the circuit breaker to be tested is greater than the slope of the time-minimum safety electrical characteristic curve at the time point, the fault is a fifth type of fault;

And if the slope of the time-electrical characteristic curve of the circuit breaker to be tested is smaller than the slope of the time-minimum safety electrical characteristic curve at the time point, judging that the circuit breaker is a sixth fault.

preferably, the time-electrical characteristic curve, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve in step S1 are all time-current characteristic curves or time-voltage characteristic curves or time-power characteristic curves or time-resistance characteristic curves.

Preferably, the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve in step S1 are obtained based on big data statistical analysis.

preferably, the step S1 includes the steps of:

s11: detecting and obtaining time-electrical characteristic curves of a plurality of standard circuit breakers;

s12: respectively aiming at different times, taking the maximum value in the time-electrical characteristic curves of the plurality of standard circuit breakers to obtain the time-maximum safe electrical characteristic curve of the circuit breaker; or, the maximum value in the time-electrical characteristic curves of the plurality of standard circuit breakers is multiplied by the maximum value coefficient to obtain the time-maximum safe electrical characteristic curve of the circuit breaker;

S13: respectively aiming at different times, taking the minimum value in the time-electrical characteristic curves of the plurality of standard circuit breakers to obtain a time-minimum safety electrical characteristic curve; or the minimum value in the time-electrical characteristic curves of the plurality of standard circuit breakers is multiplied by the minimum value coefficient to obtain the time-minimum safety electrical characteristic curve.

preferably, the method further comprises a tracking step, after the circuit breaker to be tested is judged to be unqualified, the circuit breaker to be tested is rechecked and detected, and if the circuit breaker to be tested is rechecked to be qualified, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve of the circuit breaker are corrected based on the time-electrical characteristic curve of the circuit breaker to be tested.

Preferably, for a product which is detected to be a qualified product and then is found to be a fault product, the technician analyzes the reason of the fault product, and if the fault is caused by the reason related to the detection of the circuit breaker electrical verification quality judgment method, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve of the circuit breaker are corrected based on the time-electrical characteristic curve of the fault product.

preferably, a corresponding failure electrical characteristic value on a time-electrical characteristic curve of a failure product, a maximum electrical characteristic value on a time-maximum safety electrical characteristic curve corresponding to a time point, and a minimum electrical characteristic value on a time-minimum safety electrical characteristic curve corresponding to the time point are taken;

If the fault electrical characteristic value is smaller than the maximum electrical characteristic value and larger than the maximum electrical characteristic value multiplied by the maximum fault correction coefficient, and the maximum fault correction coefficient is smaller than 1, correcting the time-maximum safe electrical characteristic curve of the corresponding time point by using the fault electrical characteristic value;

And if the fault electrical characteristic value is larger than the minimum electrical characteristic value and smaller than the minimum electrical characteristic value multiplied by the minimum fault correction coefficient, and the minimum fault correction coefficient is larger than 1, correcting the time-minimum safety electrical characteristic curve corresponding to the time point by using the fault electrical characteristic value.

According to the method for judging the electric verification quality of the circuit breaker, the time-electric characteristic curve of the circuit breaker to be detected and the time-electric characteristic curve of the qualified circuit breaker are compared and analyzed, so that whether the electric verification quality of a circuit breaker product is qualified or not can be quickly and accurately detected, and the defective circuit breaker is prevented from being regarded as a qualified product to flow out in the production process.

In addition, the fault reasons of the unqualified circuit breakers can be quickly positioned on the basis of detecting the unqualified products in the steps from S4 to S6, the unqualified circuit breakers can be conveniently modified into qualified products, and the productivity is improved on the basis of improving the proportion of the qualified products.

drawings

FIG. 1 is a flow chart of the inventive method for determining quality of an electrical verification;

FIG. 2 is a detailed flow chart of an embodiment of the present invention;

FIG. 3 is a graph of time-electrical characteristics of a good product according to an embodiment of the present invention;

FIG. 4 is a graph of time-electrical characteristics for a first type of fault according to an embodiment of the present invention;

FIG. 5 is a graph of time-electrical characteristics for a second type of fault according to the inventive embodiment;

FIG. 6 is a graph of time-electrical characteristics of a third type of fault according to the inventive embodiment;

FIG. 7 is a graph of time-electrical characteristics for a fourth type of fault according to the inventive embodiment;

FIG. 8 is a graph of time-electrical characteristics for a fifth type of fault according to the inventive embodiment;

fig. 9 is a graph of time-electrical characteristics of a sixth type of fault according to an embodiment of the present invention.

Detailed Description

The following further describes a specific implementation manner of the method for determining the quality of the circuit breaker electrical verification according to the present invention, with reference to the embodiments shown in fig. 1 to 9. The method for determining the quality of the circuit breaker electric verification created by the invention is not limited to the description of the following embodiments.

The circuit breaker generally comprises a fixed contact and a moving contact which are arranged oppositely, the fixed contact is connected to one end of a circuit through a magnetic tripping mechanism and a first wiring terminal, the moving contact is connected to the other end of the circuit through a thermal tripping mechanism and a second wiring terminal, the moving contact is connected with an operating mechanism, the operating mechanism is connected with a handle, the rotating handle can drive the operating mechanism to drive the moving contact to be in contact with the fixed contact so as to conduct the connected circuit, the operating mechanism is locked in an energy storage state at the moment, the operating mechanism is unlocked by the thermal tripping mechanism and the magnetic tripping mechanism when the circuit is overloaded and short-circuited respectively, the moving contact and the fixed contact are driven to be.

As shown in fig. 1, the method for determining the quality of the circuit breaker electric verification provided by the invention comprises the following steps:

S1: obtaining a time-minimum safety electrical characteristic curve and a time-maximum safety electrical characteristic curve of the qualified circuit breaker;

S2: obtaining a time-electrical characteristic curve of the circuit breaker to be tested;

s3: comparing the time-electrical characteristic curve of the circuit breaker to be tested with the time-maximum safety electrical characteristic curve and the time-minimum safety electrical characteristic curve respectively;

If the time-electrical characteristic curve of the circuit breaker to be tested does not have an intersection point with the time-maximum safe electrical characteristic curve and the time-minimum safe electrical characteristic curve, taking the electrical characteristic value of any time point on the time-electrical characteristic curve of the circuit breaker to be tested, and comparing the electrical characteristic value with the electrical characteristic value of the time-maximum safe electrical characteristic curve and the electrical characteristic value of the time-minimum safe electrical characteristic curve at the time point respectively;

if the electrical characteristic values of the time-electrical characteristic curve of the circuit breaker to be tested are smaller than the electrical characteristic value of the time-maximum safe electrical characteristic curve and larger than the electrical characteristic value of the time-minimum safe electrical characteristic curve at the time point, namely the time-electrical characteristic curve of the circuit breaker to be tested is always positioned between the time-maximum safe electrical characteristic curve and the time-minimum safe electrical characteristic curve, the circuit breaker to be tested is a qualified product, and otherwise the circuit breaker to be tested is an unqualified product.

according to the method for judging the electric verification quality of the circuit breaker, the time-electric characteristic curve of the circuit breaker to be detected and the time-electric characteristic curve of the qualified circuit breaker are compared and analyzed, so that the electric verification quality of a circuit breaker product can be quickly and accurately detected, and the defective circuit breaker is prevented from being regarded as a qualified product to flow out in the production process.

further, for unqualified products, the unqualified reasons can be analyzed by comparing the time-electrical characteristic curve of the circuit breaker to be tested with the time-maximum safe electrical characteristic curve and the time-minimum safe electrical characteristic curve, and the method further comprises the step of analyzing the unqualified reasons.

Step S4, if there is no intersection point between the time-electrical characteristic curve of the circuit breaker to be tested and the time-maximum safe electrical characteristic curve and the time-minimum safe electrical characteristic curve, the electrical characteristic value of any time point on the time-electrical characteristic curve of the circuit breaker to be tested is taken and compared with the electrical characteristic value of the time-maximum safe electrical characteristic curve and the electrical characteristic value of the time-minimum safe electrical characteristic curve at the time point;

If the electrical characteristic values of the time-electrical characteristic curve of the circuit breaker to be tested are all larger than the electrical characteristic value of the time-maximum safety electrical characteristic curve at the time point, namely the time-electrical characteristic curve of the circuit breaker to be tested is always positioned above the time-maximum safety electrical characteristic curve, the circuit breaker to be tested is a first type of fault (figure 4);

If the electrical characteristic values of the time-electrical characteristic curve of the circuit breaker to be tested are all smaller than the electrical characteristic value of the time-minimum safety electrical characteristic curve at the time point, that is, the time-electrical characteristic curve of the circuit breaker to be tested is always located below the time-minimum safety electrical characteristic curve, the circuit breaker to be tested is a second type of fault (fig. 5).

the step S4 of the invention has the advantages that the step S4 can judge whether the unqualified product meets the conditions of the first type of fault and the second type of fault on the basis of detecting the unqualified product in the step S3, quickly locate the fault reason of the unqualified breaker, conveniently correct the unqualified breaker into a qualified product, and improve the productivity on the basis of improving the proportion of the qualified product.

Further, the method also comprises a step S5, if the time-electrical characteristic curve of the circuit breaker to be tested and the time-maximum safety electrical characteristic curve have an intersection point, the step S5 is carried out, otherwise, the step S5 is skipped;

The step S5 includes: acquiring an intersection point of a time-electrical characteristic curve of the circuit breaker to be tested and a time-maximum safety electrical characteristic curve of the standard circuit breaker, namely acquiring the slope of the time-electrical characteristic curve of the circuit breaker to be tested at the time point when the electrical characteristic value of the time-electrical characteristic curve of the circuit breaker to be tested at the time point is equal to the electrical characteristic value of the time-maximum safety electrical characteristic curve, and comparing the slope with the slope of the time-maximum safety electrical characteristic curve of the standard circuit breaker at the time point;

If the slope of the time-electrical characteristic curve of the circuit breaker to be tested is greater than the slope of the time-maximum safe electrical characteristic curve at the time point, the fault is a third type of fault (figure 6);

if the slope of the time-electrical characteristic curve of the circuit breaker to be tested is smaller than the slope of the time-maximum safety electrical characteristic curve at the time point, the fault is a fourth type fault (fig. 7).

The step S5 of the present invention is advantageous in that the step S5 can determine whether the unqualified product meets the conditions in the third type of fault or the fourth type of fault based on the detection of the unqualified product in the step S1, and quickly locate the fault cause of the unqualified circuit breaker, so that the unqualified circuit breaker can be modified into a qualified product, and the productivity can be improved based on the improvement of the ratio of the qualified product.

Further, the method also comprises a step S6, if the time-electrical characteristic curve of the circuit breaker to be tested and the time-minimum safety electrical characteristic curve have an intersection point, the step S6 is carried out, otherwise, the step S6 is skipped;

The step S6 includes: acquiring an intersection point of a time-electrical characteristic curve of the circuit breaker to be tested and a time-minimum safety electrical characteristic curve of the standard circuit breaker, namely acquiring the slope of the time-electrical characteristic curve of the circuit breaker to be tested at the time point when the electrical characteristic value of the time-electrical characteristic curve of the circuit breaker to be tested at the time point is equal to the electrical characteristic value of the time-minimum safety electrical characteristic curve, and comparing the slope with the slope of the time-minimum safety electrical characteristic curve of the standard circuit breaker at the time point;

if the slope of the time-electrical characteristic curve of the circuit breaker to be tested is greater than the slope of the time-minimum safety electrical characteristic curve at the time point, a fifth type of fault is detected (fig. 8);

if the slope of the time-electrical characteristic curve of the circuit breaker to be tested at the time point is smaller than the slope of the time-minimum safety electrical characteristic curve, the fault is a sixth fault (fig. 9).

the advantage of the step S5 of the invention is similar to that of the step S6, and the step S6 can determine whether the unqualified product meets the situation in the fifth type fault or the sixth type fault on the basis of detecting the unqualified product in the step S3, and quickly locate the fault reason of the unqualified breaker, so that the unqualified breaker can be modified into a qualified product, and the productivity can be improved on the basis of improving the proportion of the qualified product.

Of course, if there are a plurality of intersection points between the time-electrical characteristic curve of the circuit breaker to be tested and the time-minimum safety electrical characteristic curve or the time-maximum safety electrical characteristic curve, the circuit breaker to be tested also belongs to an unqualified product.

Further, the time-electrical characteristic curve, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve in step S1 are all time-current characteristic curves or time-voltage characteristic curves.

further, the time-electrical characteristic curve, the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve in the step S1 are all time-resistance value characteristic curves.

Further, the time-electrical characteristic curve, the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve in the step S1 are all time-power characteristic curves.

Referring to the specific embodiment shown in fig. 3, the time-electrical characteristic curve, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve in step S1 are all time-resistance value characteristic curves, the time-resistance value characteristic curve of the circuit breaker to be tested is obtained by respectively collecting the current signal and the voltage signal of the circuit breaker to be tested in step S4, and the reason for the unqualified product is conveniently analyzed based on the time-resistance value characteristic curve.

Referring to fig. 4, the resistance of the first-type failed circuit breaker obtained in step S3 is wholly higher than the qualified range in the verification time due to the abnormal resistance caused by the defective process or the misassembly of the components, which indicates that the internal spot welding of the product is defective, the bimetallic resistance is larger, or the bimetallic resistance is in a wrong specification or the contact resistance of the moving and stationary contacts is larger, and the defect may cause the product to be burnt out and phase failure during normal use.

Specific analysis: this is generally caused by a small pressure of the moving contact, a wrong use of bimetal, and poor spot welding, and the overall resistance is stable and large.

Referring to fig. 5, the failure cause of the breaker with the second type of failure obtained in step S3 is due to misloading of the components, and the resistance value is wholly lower than the qualified range within the verification time, which indicates that the coil and bimetallic strip in the product may be used incorrectly and the models may not be matched.

specific analysis: the whole resistance of the circuit breaker is a wiring board contact resistance, a bimetallic resistance value, a coil resistance value and a movable contact and a stationary contact resistance, the wiring board contact resistance and the movable contact and the stationary contact resistance can only be larger, and only bimetallic and coil can be smaller, so that the resistance value is abnormal due to wrong specification and unqualified quality of the coil and the bimetallic.

referring to fig. 6, the failure cause of the breaker with the third type of failure obtained in step S5 is that the consistency of the characteristics of the parts is poor, and the resistance value first meets the qualified range and then exceeds the qualified range, which indicates that the consistency of the possible double-metal in the product is poor.

specific analysis: the whole resistance of the circuit breaker is a wiring board contact resistance, a bimetal resistance value, a coil resistance value and a moving and static contact resistance value, the wiring board contact resistance, the moving and static contact resistance value and the coil resistance value are generally stable, and abnormality may be caused by the consistency of bimetal.

Referring to fig. 8, the failure cause of the breaker with the fifth type of failure obtained in step S6 is due to a poor process, and the resistance value is lower than the qualified range and then reaches the qualified range, which indicates that there is a short circuit inside the product, and the short circuit does not occur due to the thermal bending of bimetal: this failure can result in long delays and early operation of the product.

Specific analysis: the bimetal is in a strip shape, only the head of the flexible conductor is spot-welded on the bimetal, a part of the bimetal in the strip shape is in short circuit with the flexible conductor generally, when the bimetal is heated and bent, the short circuit length of the bimetal and the flexible conductor can be changed, the resistance is firstly lower than a normal value in an acquired resistance curve, and the resistance value is slowly recovered along with the reduction of the short circuit distance.

when the time-electrical characteristic curve is drawn, the calibration table applies constant preset current (with little fluctuation) between the incoming line and the outgoing line of the circuit breaker, the preset current lasts for 10-20s, the voltage between the incoming line and the outgoing line of the circuit breaker changes along with the fluctuation of resistance, and the voltage and the current between the incoming line and the outgoing line of the circuit breaker are measured respectively to obtain the time-electrical characteristic curve of the circuit breaker to be tested.

when the electrical verification quality is detected, in order to improve the product quality, a strict detection standard is carried out and the collection of electrical characteristic data is facilitated, the electrical characteristic in the time-electrical characteristic curve of the circuit breaker to be detected can be resistance, current, voltage or power, namely, the time-resistance characteristic curve, the time-current characteristic curve, the time-voltage characteristic and the time-power characteristic curve of the circuit breaker to be detected are selected, and when any time-electrical characteristic curve is selected to pass the detection, the circuit breaker to be detected can be judged to be a qualified product. Of course, a plurality of items can be selected from the time-electrical characteristic curves for detection, and only if all the items pass the detection, the product is qualified.

Further, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve in step S1 are obtained by drawing a technician based on empirical analysis according to the characteristics of the circuit breaker.

further, as a preferable scheme, the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve in the step S1 are obtained based on a big data statistical analysis. Preferably, the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve can be obtained by the following method:

S11: detecting and obtaining time-electrical characteristic curves of a plurality of standard circuit breakers;

s12: respectively aiming at different times, taking the maximum value in the time-electrical characteristic curves of the plurality of standard circuit breakers to obtain the time-maximum safe electrical characteristic curve of the circuit breaker; or, the maximum value in the time-electrical characteristic curves of the plurality of standard circuit breakers is multiplied by a maximum value coefficient, such as 0.97, so as to obtain a time-maximum safe electrical characteristic curve of the circuit breaker;

s13: respectively aiming at different times, taking the minimum value in the time-electrical characteristic curves of the plurality of standard circuit breakers to obtain a time-minimum safety electrical characteristic curve; or multiplying the minimum value in the time-electrical characteristic curves of the plurality of standard circuit breakers by a minimum value coefficient, such as 1.03, to obtain a time-minimum safety electrical characteristic curve.

Preferably, the number of standard circuit breakers is greater than 1000, qualified products by inspection.

Further, the method comprises a following tracking step, in steps S1 to S6, after the circuit breaker to be tested is judged to be unqualified, the circuit breaker to be tested is rechecked and detected through human intervention, and if the circuit breaker to be tested is rechecked to be qualified, the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve of the circuit breaker are corrected based on the time-electrical characteristic curve of the circuit breaker to be tested. Or adding the circuit breaker to be tested into a standard circuit breaker, and recovering the time-minimum safe electrical characteristic curve and the time-maximum safe electrical characteristic curve of the circuit breaker.

And further, the following tracking step is included, for the products (such as returned products) which are detected to be qualified products and then are found to be fault products, technicians analyze the reasons of the fault products, if the faults are caused by the reasons related to the detection of the circuit breaker electric verification quality judging method, such as large contact resistance, poor spot welding, short circuit between a coil and bimetal, error spot welding of the bimetal, wrong coil installation and the like, the time-electric characteristic curve of the fault products is obtained, and the time-minimum safety electric characteristic curve and the time-maximum safety electric characteristic curve of the circuit breaker are corrected based on the time-electric characteristic curve of the fault products.

Preferably, the corresponding faulty electrical characteristic value on the time-electrical characteristic curve of the faulty product, the maximum electrical characteristic value on the time-maximum safety electrical characteristic curve corresponding to the time point, and the minimum electrical characteristic value on the time-minimum safety electrical characteristic curve corresponding to the time point are taken for different times, respectively. And if the fault electrical characteristic value is smaller than the maximum electrical characteristic value and is larger than the maximum electrical characteristic value multiplied by the maximum fault correction coefficient, and the maximum fault correction coefficient is smaller than 1, such as 0.95, correcting the time-maximum safety electrical characteristic curve of the corresponding time point by using the fault electrical characteristic value.

and if the fault electrical characteristic value is larger than the minimum electrical characteristic value and smaller than the minimum electrical characteristic value multiplied by the minimum fault correction coefficient, and the minimum fault correction coefficient is larger than 1, such as 1.05, correcting the time-minimum safety electrical characteristic curve of the corresponding time point by using the fault electrical characteristic value.

It should be noted that, when the electrical verification quality detection is performed, the detection device may simultaneously acquire ambient temperature signals, match the time-electrical characteristic curve at the corresponding temperature, and correct errors caused by the ambient temperature to obtain a more accurate test result. For example, the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve at different temperatures can be obtained by data statistics of data at different temperatures, appropriate adjustment is made when the temperature changes, and the time-electrical characteristic curve of the circuit breaker to be tested is compared with the time-minimum safety electrical characteristic curve and the time-maximum safety electrical characteristic curve at different temperatures.

The foregoing is a more detailed description of the invention, taken in conjunction with the accompanying preferred embodiments, and it is not intended that the invention be limited to the specific embodiments described. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the inventive concept, and all should be considered as falling within the protection scope of the invention.