Method for diagnosing equipment

FIELD: technical diagnostics.

SUBSTANCE: method includes, for each set of input test signals, forming of prior matching response signals for intermediate points of controlled device. Received response signals at outputs of product are compared to parameters of standard response signals and level of their match is determined, in case of mismatches broken branch of functional circuit is determined and diagnostics is repeated by substituting all formed combinations of input signals, after that diagnostics of erratic portions is started.

EFFECT: simplified method.

3 dwg

 

The invention relates to the field of technical diagnostics, in particular for diagnosing the status and Troubleshooting of electronic equipment.

The prior art methods of diagnostics and Troubleshooting of electronic equipment based on the comparison of parameters of the tested products and parameters reference products of this type (Reliability and efficiency in the technique. The guide 10 so, v.9. Technical diagnostics. Edited VLV, M.: Mashinostroenie, 1987, s-179).

The disadvantage of this method is the necessity to have on the test site products reference samples of each type of tested products. With a large range of tested products (for example, replacement of elements of complex electronic systems), this can lead to huge costs for the generation of the set of reference products.

This disadvantage is eliminated in the diagnostic method that uses a priori information in the form of a graph of States and transitions of the diagnosed system Reliability and efficiency in the technique. The guide 10 so, v.9. Technical diagnostics. Edited VLV, M.: Mashinostroenie, 1987, s-153).

The disadvantage of this method is that when unequal probabilities of States of the diagnosed equipment is difficult and sometimes impossible of realitv shall be even quasi-optimal ways of diagnosing failures of the items tested. In addition, the formation of diagnostic tests in the diagnosis of complex electronic equipment with overlapping branches functional schemes and multilevel structure presents a significant challenge.

The technical result from the use of this method is to simplify the implementation of procedures for diagnostics and Troubleshooting complex electronic devices by providing target location of a fault in the design of the controlled device.

This technical result is achieved as follows.

Method for the diagnosis of complex electronic devices based on alternately fed to the inputs of the device pre-formed sets of input test signals and the equivalent bodies of the response signals at the outputs of the test object, wherein for each set of input test signals pre-form equivalent of the aggregate of the response signals for the intermediate points, corresponding to the outputs of the cascades (functional layers) branches of scheme products, the totality of the response signals identify the type components with geometric position of this component part on the surface of the printed circuit Board of the controlled products and branch functional CX is we, for intermediate points which formed these signals serves combinations of test input signals to the input contacts of diagnosed products, receive the equivalent signals in response to output contacts diagnosed products, compare parameters measured signal response with parameters pre-formed reference signal response for this type of product, determine the degree of coincidence of the measured and reference signals, the detection of mismatches record numbers of output contacts with nesovmestimi signals and determine the branch functional diagram of a product containing the problem, repeat the procedure diagnostic products by searching all pre-formed combinations of input signals and determine in this way all the rooms of the output contact of the product with nesovmestimi signals and non functional branches schema of the product with the alleged fault, in the absence of mismatched output signals diagnosed product qualify as healthy, and in the presence of mismatches go to diagnostics places malfunction, choose combinations of input signals, identified by the formation of the tests with the testing of suspected failure of the branches of the functional circuit, consistently asking combination of the project for the input test signal input contacts products which inputs diagnosed branches of the functional schema of the product, form specifying the determination of the parameters of the response signals in the intermediate points of diagnosed branches of the functional schema of the product when you step transitions in the direction from output to inputs of the branches of the functional schema of the product, determine the parameters of the response signals in said intermediate points of the branches of the functional design of the product, compare the parameters of the response signals at intermediate points with pre-formed criterial parameters of the reference signals for the same points, determine the interval of transition from the mismatch of signals on a single step to the coincidence signal at the next step diagnosed branch functional diagram of the product, identify the type and location of the identified faulty components parts diagram diagnosed product, repeat the Troubleshooting procedure for the other branches of the functional circuit diagnostic products to the full detection, identification and localization of all faults and form instructions on elimination of detected errors.

The implementation of the inventive method is illustrated in the block diagram of the automated diagnostic system is shown in figure 1. The system 1 is diagnosed, the product 1 to the WMO is the main contacts of which are connected to the source 2 input test signals, to the output contacts and the intermediate points for the diagnosed unit 1 is connected to the inputs of the probes 3 of the response signals, the input source 2 input test signals and the outputs of the probes 3 of the response signals are connected to the respective outputs and inputs of the computer 4, the output of which is the system output figure 1.

Before implementing the inventive method in the computer 4 install the software that implements the algorithm of the diagnostic system 1 according to the claimed method.

When preparing the system 1 is one of the known methods are generated diagnostic tests, including:

1) description of parameter combinations of the input signals to be fed to the input contacts to check the state of the branches of the functional scheme of this type of inspected products;

2) description of parameter combinations of the output signals on the output pins and the intermediate points of diagnosed branches of the functional circuit products (identified with numbers of output contacts, type and position of the component parts of products, respectively);

3) description of instructions step-by-step transitions at intermediate points of the branches of the functional circuit diagnostic products;

4) description of the sequence enumeration of combinations of input signals, asked on input pins when diagnosing the condition and di is the diagnosis of malfunctions of the product.

These data can be formed using one of the methods known from the prior art (for example, on the basis of reference samples of products of this type, used once to generate tests based on the use of equivalent models, products and so on).

After preparing the system it is connected to diagnosed sample, as shown in figure 1. Run the program for the automated implementation of the algorithm and perform all the operations of the claimed method. Instructions for transitions to measurements at intermediate points and other dialog procedures carried out by issuing the appropriate message to the operator on the monitor screen, part of the computer 4.

As of 2 sources of input test signals (depending on the type of diagnostic products) can be used generators parallel code combinations of signals, programmable pulse generators, signal generators, special forms, programmeprogramme generators of high-frequency signals and other programmeprogramme the devices known from the prior art.

As a measure 3 of the response signals with the output contacts and the intermediate points of the product 1 can be used (depending on the type of diagnostic products) digital oscilloscopes, spectrum analyzers, logically the analyzers, signature analyzers and other digital measuring devices known from the prior art.

As the computer 4 in the system of figure 1 can be used personal computers required performance known from the prior art, equipped with appropriate software and interface devices for connecting the sources of the 2 inputs and 3 meters of the response signals.

Thus, the claimed method provides receiving a new positive effect, implying rapid unambiguous detection of faults in the composition of the functional complex of inspected parts and forming instructions on removing the identified fault - indicating the type of fault components and its location in the structure of the product.

To illustrate the application of the claimed method consider the diagnostic procedure of electronic products, representing a printed circuit Board with the implementation of an it functional logic. Scheme of the test object used in the example shown in figure 2. As is evident from figure 2, the structure of the device are two Autonomous logic circuits, which can be described by logical equations

where Y1and Y8- input and output connectors;

Y1-Nand Y8-N- the appropriate signals on the pins "N" connectors Y1and Y8;

Y2and Y4- electronic circuit elements 2 that implement the logical function (ab);

Y3and Y5- electronic elements that implement a logic function (a+b);

Y6and Y7- electronic elements that implement the logical function

Since the logical chain, ending with outputs Y8-8and Y8-14according to their functions and composition is identical (see scheme 2), tests to diagnose the condition of each of the circuits will also be identical. Diagnostic tests to diagnose the condition and to diagnose malfunctions of the circuit of figure 2 is shown in the table presented in figure 3.

Before diagnosing one of the known methods are generated diagnostic tests, representing a combination of the values of the signals on the input pins of the diagnostic object (contact Y1-1, Y1-3, Y1-5and Y1-7- for the first logical circuit, and the contacts Y1-9, Y1-10, Y1-11and Y 1-12- for the second logical circuit schematic figure 2), and the corresponding values of the signals on the output pins of the diagnostic object (contacts Y8-8and Y8-14and values of signals in the intermediate points of the circuit (for example, at the contacts Y6-1and Y6-2for the first logical circuit and the contacts Y7-1and Y7-2for the second logical circuit). Combination of values of the test signals at the input pins change from beat to beat (see table 3) so that were tested all possible operating state of the controlled product. In this example this is represented in the form of logic States of the test signals at the input pins of the circuit of figure 2, changing in 16 cycles (the first four columns of table 3). Each combination of test input signals in good condition controlled logic circuit 2 will meet the criteria values of the response signals on the output pins Y8-8and Y8-14(right column of table 3) and at intermediate points Y6-1, Y6-2, Y7-1, Y7-2(two penultimate right columns of table 3). Besides this, as the original data before the diagnosis is determined and fixed position devices Y1The...Y81on the Board (which can be set, for example the EP, the values of the orthogonal coordinates x-y position of the radio electronic elements on the PCB surface, the number "z" side of the PCB or any other way of describing the coordinate position REE)to provide a clear indication to the operator the position of the faulty element in the design of the diagnostic object.

Another type of a priori information used in the composition of the initial data for diagnostic products are (computational or experimental) characteristics of reliability "Ri" branches schemes diagnosed products. These values are used as weights for the automated generation sequencing diagnostics branches of the circuit to more quickly find fault. In this example, the schema in figure 2 as such weights will be used, the values of probability of failure (p2=p4for branches devices Y2and Y4and (p3=p5for branches with devices Y3and Y5respectively.

The procedure for diagnosing the state of the controlled products figure 2 begins with the inclusion of the object diagnostic 1 diagnostic system 1. In memory of the computer 4 of the system 1 is recorded diagnostic tests according to figure 3 and listed additional source data (the op is Sania location coordinates of circuit elements x, y, z and probability of failure pi" branches scheme 2). According to the program of the computer 4 of the system 1 through the device formation test 2 on the diagnostic object 1 (scheme 2) turn the beat for beat given the test signals, the values of which are given in the first four columns of table 3. With output contacts of the control object 1 (with contacts Y8-8and Y8-14scheme 2) using a 3 meter in each step are determined by the values of the response signals and the measured values from the output of the meter 3 are received in the computer 4 for comparison with the criterion values (last column of table 3).

If in each of the cycles the values of the response signals obtained by measuring 3 will coincide with the values of criteria signals table 3, for the passage of the last (16th stroke table 3) diagnostic system figure 1 describes the status of this instance in the control as "healthy", usable for its intended purpose.

If one of the cycles the response signals received from one of the outputs diagnosed (with output Y8-8or Y8-14scheme 2) will not coincide with the criterion values (with values given in the last column of table 3), the diagnostic system 1 makes the waiver diagnostique the th sample of the product and go to diagnostics fault.

The Troubleshooting will occur according to the following algorithm.

The discrepancy between the measured signal response and the criteria values of a signal on one of the outputs (the last column of table 3) allows to determine the faulty part (the failed logical circuit see figure 2) object schema diagnosis that is associated with this output.

The logic circuit ended output with the identified symptom (exit Y8-8or Y8-14figure 2) is a tree, branching towards the inputs. In each of the branches of the "tree" potential failure.

In this example 2 assume that the fault detected in the logical circuit associated with the output Y8-8. Then the cause of the fault can be or failures of devices Y6, Y2and Y3or damage electrical connections between the contacts of the circuit branches.

To clarify the failure to produce the measurement signal response in the intermediate points of the faulty circuit (in our case, the points Y6-1and Y6-2) and compare them with the values of the criteria of the response signals for these points (the penultimate right columns of table 3).

Upon detection of coincidence of the response signals at these points with criterial signals qualify malfunction Y6(in the ar receives signals, matching criterion, and the output is a mismatch, indicating failure).

When the mismatch signal on one of the intermediate points with criterial signals qualifies the failure of the earlier part of the branch, the output of which is the contact. For example, if the discrepancy between the contact Y6-1the problem in the device Y2(or in the electric circuit between the contacts Y6-1and Y2-3).

In order to expedite the Troubleshooting for complex iterative schemes diagnostic objects, the sequence of display sub-pixels at each level of the scheme (at each node of the branch - see figure 2) is based on a priori information about the probability of failure Ri" previous parts of the schema. For example, if the probability of failure p2" device Y2more than the probability of failure p3" device Y3then you first need to diagnose the branch containing the device Y2(i.e. by measuring the signals at the points Y6-1and Y2-3), and then in the branch containing the device Y3.

Troubleshooting electrical circuits between the contacts is performed by measuring the response signals at the contact end and the contact start (for example, contact Y8-8and Y6-3, Y6-1and Y2-3etc) each electric C is PI controlled branches.

Accelerate diagnostics is also provided by the fact that after the detection of the defective part of the scheme is based on a priori information about the location of the circuit components of the product design) indication of the place of connection of the measuring probe device 3 (see Fig 1) to a corresponding intermediate point of the defective portion of the schema.

Thus:

1) on the basis of comparison of the response signals at each output diagnosed products with the corresponding criterion values of the response signals revealed the presence of a product defect and is determined defective part of the product associated () with data output;

2) refinement of the fault is performed by measuring the response signals in the intermediate points of the branches of the defective portion of the circuit of the product and comparison with criterion values of the response signals for these points, and the display sub-pixels is sequentially (steps) in the direction from output to inputs of the branches of the schema of the product;

3) the sequence view points belonging to different branches of the products, taking into account a priori information about the probability of failure is diagnosed branches of the defective portion of the circuit products, the top view of the branches that have a higher probability of failure;

4) to detect failures of electrical circuits in the tick points faulty part of the circuit diagnostics of failures in the intermediate points produce twice the contact end and the contact start electrical connections (electrical circuit), belonging to the intermediate point of the scheme;

5) to speed up the procedure of finding fault, after identifying the faulty part of the circuit is made (based on the a priori description of the location of the schema elements in the design of the product - for example, on the surface of the printed circuit Board) identification of the location of the next intermediate point, and issued instructions to the operator (for example, on a computer monitor 4 system figure 1) about the location of the measuring points.

This diagnostic procedure according to the claimed method provides better performance fault diagnosis, a higher diagnostic accuracy and rapid convergence process of finding fault.

Method for the diagnosis of complex electronic devices based on alternately fed to the inputs of the controlled devices are pre-generated sets of input test signals and used as criteria for the operability of the circuitry of the unit equivalent of the populations of the response signals at the outputs of the controlled device, wherein for each set of input test signals pre-form equivalent of the aggregate of the response signals DL the intermediate points, the respective outputs of the stages of the branches of the circuit controlled device, the combination of the response signals identify type integral part of the controlled device, with geometric position of this component part on the surface of the printed circuit Board of the controlled device and branch functional diagram of a controlled device, for intermediate points which formed these signals serves combinations of test input signals to the input contacts of the controlled device receives an equivalent signals in response to the output contacts of the controlled device, comparing the parameters measured signal response with parameters pre-formed reference signal response for the given type of the controlled device, determine the degree of coincidence of the measured and reference signals of the response, the detection of mismatches non fixed output contacts with nesovmestimi signals and determine the branch functional diagram of a controlled device, containing a fault, repeat the procedure for diagnosing the state of the controlled device by searching all pre-formed combinations of input signals and determine in this way all the rooms of the output contacts of the controlled device with nesovmestimi signals and non f the purpose ground receiving stations of the branches of the circuit of the controlled device with the alleged fault, in the absence of mismatched output signals controlled device qualify as healthy, and in the presence of mismatches controlled device qualify as defective and go to diagnostics places malfunction, choose combinations of input signals, identified by the formation of the tests with the testing of suspected failure of the branches of the functional circuit, consistently ask combinations of input test signals to the input contacts of the controlled device, which inputs diagnosed faulty branches of the functional circuit of the controlled device, form specifying the determination of the parameters of the response signals at intermediate points diagnosed faulty branches of the functional circuit of the controlled device when you step transitions in the direction from output to inputs of the branches of the functional circuit of the controlled device, determine the parameters of the response signals in said intermediate points of faulty branches of the functional circuit of the controlled device, comparing the received parameters of the response signals at intermediate points with pre-formed criterial parameters of the reference signals for the same points, determine the interval of transition from the mismatch of signals in one step to solpadine the signal on the next step to diagnose the faulty branch functional diagram of the controlled device, identify the type and location of the identified faulty part of the circuit controlled device, repeat the Troubleshooting procedure for the other defective branches of the functional circuit of the controlled device to complete the detection, identification and localization of all faults and form instructions on elimination of detected errors, and the sequence around the branch of a defective portion of the circuit of the controlled device is performed in descending order based on a priori probabilities of failure pibranches of the circuit controlled device.



 

Same patents:

FIELD: measuring equipment.

SUBSTANCE: device has block for forming control and stimulation signals, block for forming standard signals, multiplication blocks, frequency transformer, phase rotator, commutator, frequencies grid generator, integrators, blocks for square involution, adder, normalization block, key, analog-digital converter, comparison circuits, memory blocks, registers, information output block, interval estimation block (for setting lower and upper limits of trust range for each measured value of mutual difference coefficient of distorted and standard signals) and block for analysis of number of support values of mutual difference coefficient (to exclude from further processing results of measurements, for which within limits of trust interval number of support values of coefficient exceeds allowed limit).

EFFECT: higher precision.

2 cl, 2 dwg

FIELD: automatic control.

SUBSTANCE: device has first and second analog-digital converters, first and second coefficients forming blocks, first and second multiplication blocks, counter, first and second integrator, control effect forming device, division block, buffer and registering block, while coefficients forming blocks are made in form of digital filters and all remaining blocks of device are made digital.

EFFECT: higher precision, higher resistance to interference.

1 dwg

FIELD: automated control and diagnostics systems.

SUBSTANCE: first variant of complex includes control computer, mating block, commutator, local data exchange main, tests forming block, logical analyzer, signature analyzer, synchronization block, digital oscillographs block, special form signals programmed generators block, programmed power-sources block. Second variant of complex additionally includes block for forming high-frequency test signals and block for measuring high-frequency signals.

EFFECT: broader functional capabilities, higher efficiency, higher reliability.

2 cl, 2 dwg

FIELD: measuring equipment.

SUBSTANCE: as a source of standard signal not separate generator of test signal according to known code structure is used, but a component of modem, to provide for substantial simplification of process under unfavorable conditions.

EFFECT: higher efficiency.

1 dwg

FIELD: instrumentation engineering; serviceability check of multichannel communication systems.

SUBSTANCE: proposed equipment includes personal computer, multiplexing switch, circuit checkup unit, control unit, multichannel comparison unit, virtual standard, switching unit, output signal shaper, multiplexer, and normalizing unit that has voltage meter and circuit meter.

EFFECT: enlarged functional capabilities of device.

3 cl, 1 dwg

FIELD: mechanical engineering.

SUBSTANCE: method comprises determining variations of the parameter during acceleration and deceleration of the actuator. The device comprises generator and OR-NOT unit, the inputs of which are connected with the outputs of the relay. The output of the relay is connected with the input of the generator.

EFFECT: enhanced accuracy of the method and simplified device.

3 dwg

FIELD: electric measurements, applicable in check-up of tram and trolleybus electric apparatuses in the process of manufacture and in service.

SUBSTANCE: current in the current source is fed to the current winding of the current relay from the rectifier via a key, choke, shunt. The device uses a pulse-width modulator that controls the keys, slowly varying voltage is applied to the modulating input of the pulse-width modulator that is preliminarily modulated by the rectifier ripple voltage. Besides, use is made of a sample-release circuit of operate (release) currents and voltages. The signals from these circuits are fed to indicators via analog-to-digital converters.

EFFECT: reduced error of determination of operate and release current and voltage relays, enhanced capacity of check-up in the device due to reduced ripples of the source of smoothly varying current.

2 cl, 4 dwg

FIELD: measuring and monitoring technique, possibly monitoring of different objects.

SUBSTANCE: system includes control unit, unit for calling testing programs, coupling unit, measuring unit, test stimulation unit, power sources, unit for distributing signals, memory unit, N matching units, N testing program units. Each testing-program unit has evaluation circuit and two memory devices.

EFFECT: lowered volume of equipment, simplified organization of monitoring process and development of software.

1 dwg

FIELD: automatic control, applicable in systems with excessive quality of transducers, for example, accelerometers, a failure of one of which should not result in a failure of the control system.

SUBSTANCE: the method is based on a periodic check-up of relation between the measured parameters of motion characterizing the correct operation of the transducers, fixation of the moment of failure of the relation, comparison of the readings of the transducers at this moment and at the moment preceding the moment of disturbance of the relation, and determination of the failed transducer by the results of the comparison.

EFFECT: expanded functional potentialities due to possibility of determination of the failed transducer in any excess system.

1 dwg

The invention relates to the field of non-destructive control of discontinuities, irregularities and other defects of material or product groups

FIELD: automatic control, applicable in systems with excessive quality of transducers, for example, accelerometers, a failure of one of which should not result in a failure of the control system.

SUBSTANCE: the method is based on a periodic check-up of relation between the measured parameters of motion characterizing the correct operation of the transducers, fixation of the moment of failure of the relation, comparison of the readings of the transducers at this moment and at the moment preceding the moment of disturbance of the relation, and determination of the failed transducer by the results of the comparison.

EFFECT: expanded functional potentialities due to possibility of determination of the failed transducer in any excess system.

1 dwg

FIELD: measuring and monitoring technique, possibly monitoring of different objects.

SUBSTANCE: system includes control unit, unit for calling testing programs, coupling unit, measuring unit, test stimulation unit, power sources, unit for distributing signals, memory unit, N matching units, N testing program units. Each testing-program unit has evaluation circuit and two memory devices.

EFFECT: lowered volume of equipment, simplified organization of monitoring process and development of software.

1 dwg

FIELD: electric measurements, applicable in check-up of tram and trolleybus electric apparatuses in the process of manufacture and in service.

SUBSTANCE: current in the current source is fed to the current winding of the current relay from the rectifier via a key, choke, shunt. The device uses a pulse-width modulator that controls the keys, slowly varying voltage is applied to the modulating input of the pulse-width modulator that is preliminarily modulated by the rectifier ripple voltage. Besides, use is made of a sample-release circuit of operate (release) currents and voltages. The signals from these circuits are fed to indicators via analog-to-digital converters.

EFFECT: reduced error of determination of operate and release current and voltage relays, enhanced capacity of check-up in the device due to reduced ripples of the source of smoothly varying current.

2 cl, 4 dwg

FIELD: mechanical engineering.

SUBSTANCE: method comprises determining variations of the parameter during acceleration and deceleration of the actuator. The device comprises generator and OR-NOT unit, the inputs of which are connected with the outputs of the relay. The output of the relay is connected with the input of the generator.

EFFECT: enhanced accuracy of the method and simplified device.

3 dwg

FIELD: instrumentation engineering; serviceability check of multichannel communication systems.

SUBSTANCE: proposed equipment includes personal computer, multiplexing switch, circuit checkup unit, control unit, multichannel comparison unit, virtual standard, switching unit, output signal shaper, multiplexer, and normalizing unit that has voltage meter and circuit meter.

EFFECT: enlarged functional capabilities of device.

3 cl, 1 dwg

FIELD: measuring equipment.

SUBSTANCE: as a source of standard signal not separate generator of test signal according to known code structure is used, but a component of modem, to provide for substantial simplification of process under unfavorable conditions.

EFFECT: higher efficiency.

1 dwg

FIELD: automated control and diagnostics systems.

SUBSTANCE: first variant of complex includes control computer, mating block, commutator, local data exchange main, tests forming block, logical analyzer, signature analyzer, synchronization block, digital oscillographs block, special form signals programmed generators block, programmed power-sources block. Second variant of complex additionally includes block for forming high-frequency test signals and block for measuring high-frequency signals.

EFFECT: broader functional capabilities, higher efficiency, higher reliability.

2 cl, 2 dwg

FIELD: automatic control.

SUBSTANCE: device has first and second analog-digital converters, first and second coefficients forming blocks, first and second multiplication blocks, counter, first and second integrator, control effect forming device, division block, buffer and registering block, while coefficients forming blocks are made in form of digital filters and all remaining blocks of device are made digital.

EFFECT: higher precision, higher resistance to interference.

1 dwg

FIELD: measuring equipment.

SUBSTANCE: device has block for forming control and stimulation signals, block for forming standard signals, multiplication blocks, frequency transformer, phase rotator, commutator, frequencies grid generator, integrators, blocks for square involution, adder, normalization block, key, analog-digital converter, comparison circuits, memory blocks, registers, information output block, interval estimation block (for setting lower and upper limits of trust range for each measured value of mutual difference coefficient of distorted and standard signals) and block for analysis of number of support values of mutual difference coefficient (to exclude from further processing results of measurements, for which within limits of trust interval number of support values of coefficient exceeds allowed limit).

EFFECT: higher precision.

2 cl, 2 dwg

FIELD: technical diagnostics.

SUBSTANCE: method includes, for each set of input test signals, forming of prior matching response signals for intermediate points of controlled device. Received response signals at outputs of product are compared to parameters of standard response signals and level of their match is determined, in case of mismatches broken branch of functional circuit is determined and diagnostics is repeated by substituting all formed combinations of input signals, after that diagnostics of erratic portions is started.

EFFECT: simplified method.

3 dwg

Up!