DE102004032966A1 - Communication network e.g. LAN, examining/monitoring or analyzing device, has memory storing bus or analogue value signals, and display unit indicating deviation/trend of deviation between actual and reference data/errors in network - Google Patents

Abstract

The device has a control station with which members can communicate via a bus system (4). A test control unit records a measuring point-specific bus signal and/or an analogue measuring value signal at measuring points in a network in a reference condition. A memory unit stores the signals as a reference data. A display unit indicates a deviation or trend of deviation between actual and reference data or errors in the network. An independent claim is also included for a method for examining/monitoring or analyzing a communication network.

Description

The The invention relates to an apparatus and a method for checking and / or monitoring or analysis of a communication network.

In a communication network communicates a plurality of participants via a Bus system with each other. The communication network may be For example, to act a server in conjunction with a Variety of clients, here PCs, printers, etc. stands. At the network For example, it is a LAN. Increasing communication networks also used in process automation. About the communication network is e.g. a complete manufacturing plant for the production of pharmaceutical or chemical products controlled. The control is done by a Process control center off; It communicates with the connected subscribers via a bus system. which are in particular field devices and / or actuators. Communication takes place on the basis of a standardized communication protocol instead of. Examples are Profibus PA and Fieldbus Foundation to call.

Is working the bus system or one of the participants is faulty, that's the way it is ever by size the communication network very time consuming, the source of error to detect. Depending on the nature of an error, there is a risk that the entire plant comes to a standstill, which follows too Production losses and significant profit losses. The operator of a process plant is therefore to a great extent interested that the system works steadily and error-free. The Invention proposes a method and a device that provides an undisturbed, steady Function of the process plant or communication network with ensure the connected participants. Can be achieved this by the fact that imminent errors in advance the actual error case / failure of the subscriber or the bus system detected or be made recognizable so that appropriate action can be taken early to tackle the problem.

Of the Invention is based on the object, an apparatus and a method to propose a predictive maintenance and fault / failure analysis in a communication network with a large number of subscribers possible is.

The Task is solved by a device consisting of at least one Control center, at least one bus system and several participants that exists over the bus system communicate with the control center. Furthermore, it is provided: at least a tester that in a desired state of the communication network at defined measuring points of the communication network in each case at least one measuring point-specific Detected bus signal and / or at least one analog measured value signal, the tester becoming a later Time in an actual state of the communication network the corresponding measuring point-specific bus signals and / or the analog measured value signals recorded and stored as actual data and / or provides; a Memory unit in which the detected measuring point specific bus signals and / or the analog measured value signals stored as desired data become; a display unit, via the one deviation or a trend deviation between the actual data and the target data or error or imminent error in the Communication network is communicated to the service personnel or be communicated.

• – einen Spannungspegel, wobei die Versorgungsspannung des Bussystems der Versorgungsspannung der Teilnehmer entspricht
• – die Signalstärke des Kommunikationsprotokolls – hierbei entspricht der Spannungspegel einem High/Low Signal
• – die Induktivitäts- und/oder Kapazitätswerte eines Netzwerkstranges zwischen dem Segmentkoppler und den Teilnehmern (den Feldgeräten in einem in einer Prozessanlage installierten Verbund von Feldgeräten/Aktoren oder den Clients in einem PC-Netzwerk)
• – die Stromaufnahme eines Netzwerkstrangs
• – Störspannungen/EMV RMV Signale
• – das Kommunikationsprotokoll
• – die Busprotokolle, die technologieabhängige Sollwerte verkörpern.

The measuring point-specific bus signals can be very different signals, eg

• - A voltage level, wherein the supply voltage of the bus system corresponds to the supply voltage of the participants
• - The signal strength of the communication protocol - here the voltage level corresponds to a high / low signal
• The inductance and / or capacitance values of a network string between the segment coupler and the nodes (the field devices in a network of field devices / actuators installed in a process plant or the clients in a PC network)
• - The current consumption of a network strand
• - Interference voltages / EMC RMV signals
• - the communication protocol
• - The bus protocols, which embody technology-dependent setpoints.

According to an advantageous development of the device according to the invention, an evaluation unit is provided which recognizes errors or impending errors in the communication network on the basis of a deviation or based on a tendency to deviate the actual data from the desired data and makes proposals for countermeasures or corresponding proposals for display brings. The measures are measures in the direction of 'Predictive Maintenance' or 'Advanced Diagnostics'. So a suggestion could be: "replace the participant XYZ within the next X months by a new participant" or 'The maintenance cycle should be increased / reduced by the participant YXZ by x months become".

Prefers a data logger is used to record the actual data.

A advantageous embodiment of the inventive device suggests - as already previously said - before, that the control center is a server and the participants is about PCs. Alternatively, it may be at the control center to a Process control system and at the participants to field devices for determination and / or monitoring a physical or chemical process variable and / or actuators (pumps, Valves).

Prefers are several PCs or field devices arranged in a network thread. A network thread consists of a network switch and several PCs or alternatively one Segment coupler and several field devices and / or actuators. The PCs or the field devices / actuators are either electrically wired together in a network string, or they communicate with each other wirelessly - swap Information via radio. Under a network strand is thus the wiring between a segment coupler and the subscribers to understand. The 'cabling' can be - as already mentioned - to one electrical or wireless wiring / networking between a PLS (process control system) or a server via possible segment couplers or network switches and the participants in the communication network.

Under A participant is generally a field device (a valve, a meter, an actuator) Client (eg a PC: = personal computer, etc.) to understand.

These it is the communication network z. B. to a composite Field devices and / or Actuators, as used in process automation for control and regulation used by process equipment, the bus signals are either electrical analog sizes and / or bus or communication protocols. In the process and Automation technology, different standards of bus and communication protocols used. Exemplary are at this Job called Profibus PA and Fieldbus Foundation.

The evaluation unit and / or the display unit is a software tool. One tool that may be used in conjunction with the present invention, for example, is the IBA Tool - Installed Base Analyst - a spare parts finder tool offered and distributed by the Endress + Hauser Group. Described is this IPA tool in detail in the non-prepublished German patent application DE 103 22 080.1 ,

According to one preferred embodiment of the inventive device is at the tester to a gauge for detecting an electrical variable, eg. B. an analogue voltage or current value, or a measuring device for detecting communication-typical Bus signals.

• – in einem Soll-Zustand des Kommunikationsnetzwerkes werden bzw. wird an definierten Messstellen des Kommunikationsnetzwerkes jeweils zumindest ein messstellenspezifisches Bussignal und/oder ein analoges Messwertsignal bestimmt;
• – die bestimmten messstellenspezifischen Bussignale und/oder die analogen Messwertsignale werden als Soll-Daten abgespeichert;
• – zu einem späteren Zeitpunkt werden in einem Ist-Zustand des Kommunikationsnetzwerkes die entsprechenden messstellenspezifischen Bussignale und/oder die analogen Messwertsignale erfasst und als Ist-Daten abspeichert und/oder bereitstellt;
• – eine Abweichung oder eine tendenzielle Abweichung zwischen den Ist-Daten und den Soll-Daten wird erkannt;
• – die Abweichung bzw. die tendenzielle Abweichung wird zur Analyse des Kommunikationsnetzwerkes herangezogen.
• – ggf. werden Vorschläge für Maßnahmen zur Beseitigung von Fehlern oder sich anbahnenden Fehlern dem Bedienpersonal bereitgestellt.

In addition, the object is achieved by a method comprising the following method steps:

• In a desired state of the communication network, at least one measuring point-specific bus signal and / or an analog measured value signal are respectively determined at defined measuring points of the communication network;
• - The specific measuring point specific bus signals and / or the analog measured value signals are stored as desired data;
• At a later time, in an actual state of the communication network, the corresponding measuring point-specific bus signals and / or the analog measured value signals are recorded and stored as actual data and / or provided;
• A deviation or a trend deviation between the actual data and the desired data is detected;
• - the deviation or trend deviation is used to analyze the communication network.
• - where appropriate, proposals for measures to remedy errors or impending errors are made available to operating personnel.

at the inventive The method is therefore a preventive method Examination / Verification (predictive Maintenance) and subsequent troubleshooting in Kommunikatsnetzwerken. The invention thus enables the exact analysis of an existing communication network. As a general rule The invention relates to all kinds of communication networks; However, it is preferably used in fieldbus technology.

The Invention allows the preventive and early Detection of possible Errors and vulnerabilities within a network (preferred in process automation). The aim is to have a high guarantee that no errors occur in the process. With the help of evaluation software allows it the invention, predictive reviews in terms of default frequencies individual participant in a manufacturing plant or in a communication network perform.

The bus signals described above are detected by means of a bus monitor, an oscilloscope, a voltage, capacitance, inductance and current measuring device or by means of communication-typical technical measuring devices. The acquisition of data and measured values is typically stored in the measuring and evaluation devices (data loggers); Alternatively, the detection can also be done manually. Preferably, the acquisition of the desired data during initial commissioning or alternatively when restarting the communication network is to be made. The data acquisition can thus also be carried out in an already existing communication network.

Around to obtain the target data under real reference conditions is it is expedient the data during the operation of the communication network, in particular during the Operation of all associated To determine system components such as motors, pumps, control valves, etc. This approach has the advantage that all possible interference on the network topology can be included or that these actually exist Disturbances in the Reflect target data. The disturbing influences are, for example to EMC / RMI signals. All target data is preferred per measuring point stored in a database. For the target data, as later with the actual data, it is therefore measurement-specific Bus signals or to measurement-specific analog measured value signals. Preferred measuring points are in particular the segment couplers or Subscriber of the communication network.

• – Messstellenort
• – Gerätedaten (Typ, Geräte-Nr., usw.)
• – Bussignale
• – Messwertdaten ( wie zuvor beschrieben)
• – Typische Soll-Daten (entsprechend den Herstellerangaben)
• – Max/Min Werte
• – Toleranzwerte/Grenzwerte
• – Fehlerliste nach Fehlerbild (abhängig von den Soll-Daten und der Technologie, etc.)
• – eine Zeitmarke, die angibt, wann die Daten erfaßt wurden.

The data (nominal or actual data) is preferably recorded in a database in accordance with the structure listed below. The database is, for example, the so-called IBA tool, which is offered and distributed by the Endress + Hauser Group. IBA is the abbreviation for Installed Base Analyst:

• - Measuring point location
• - Device data (type, device no., Etc.)
• - Bus signals
• - measured value data (as described above)
• - Typical nominal data (according to the manufacturer's instructions)
• - Max / Min values
• - Tolerance values / limit values
• - Error list after error image (depending on the target data and the technology, etc.)
• A timestamp indicating when the data was collected.

at the detection of the physical bus signals, e.g. the electricity and the voltage values, etc. are also in a database, the target data for the respective Participants added. The target data can preferably be refer to the plant and technology typical data sheets. Are these not available, the actual data is in a defined state of the communication network and stored as nominal data. additional Target data (e.g., for checking the measured data) the corresponding data sheets be taken from the network technology used. The system-typical, measuring point-specific bus signals are metrologically recorded and stored as target data, insofar Do not be the one for below or above the required values. Here you can directly at the initial recording of the target data already in the system or in the network existing errors are detected. These become error lists eliminated. For this purpose, the actual data by a re-capture the measuring point-specific bus signals or the measuring point-specific analogue Measurement signals recorded.

By the recurring exam and capturing the data can be a history of the measurements of the communication network be stored in the database. This becomes a forward-looking Maintenance possible.

Of the Comparison of the actual data with the target data including Tolerance values can either automatically via an evaluation unit or done manually. When falling below the specified tolerance values appropriate error logs for the affected measuring points output. Also preferred is a suggestion list with measures issued for the elimination of the occurred or imminent error. The error logs or debugging suggestions are dependent on from the corresponding technology-typical measures at the initial admission the target data recorded.

Out the history of the data leaves also recognize whether the actual data show the tendency from the Tolerance range to drift away the target data. Based on the speed the changes can be continue to recognize at what time the tolerance limits with high probability exceeded become. It can Thus, trend statistics are created by means of the invention. These will subsequently to the introduction of preventive measures for the purpose of avoidance of failures used.

By the evaluation of the data receives the service personnel or the operator of the communication network an overview of the state of the network based on history data and its functionality and a general overview of the State of the communication network. According to the invention are therefore statistical calculations about Failure probabilities and predictive uptime calculations possible.

• – Messstelle
• – Netzwerkstrang
• – Geräteyp
• – Abweichung vom Sollwert
• – Unter/Überschreitung des Sollwerts/der Sollwerte
• – Erreichen des Grenzwerts/der Grenzwerte
• – Messstelle in Ordnung
• – Fehlerprotokoll
• – Maßnahmenkatalog zur Behebung des Fehlers.

The evaluation itself can be done individually or cumulatively according to the following parameters:

• - Measuring point
• - Network strand
• - Device type
• - deviation from the setpoint
• - Under / exceeding the setpoint / setpoints
• - reaching the limit / limits
• - Measuring point in order
• - Error log
• - Measures catalog to correct the error.

The Output of the evaluation can be adjusted and filtered as desired be, e.g. Is it possible, only faulty measuring points or all measuring points of a network string issue. By specifying a plant-specific tolerance value - this corresponds preferably a desired value for all occurring communication disturbances for the communication network - receives the service personnel or the operator a reliable assessment of the general reliability of his communication network and so that his process plant.

The The invention will be explained in more detail with reference to the following figures. It shows:

1 : a schematic representation of the device according to the invention,

2 a flowchart for visualizing the inventive method in the initial start-up or when restarting the communication network and

3 : a flow chart for visualizing the inventive method in the recurrent review of the communication network.

1 shows a schematic representation of the inventive device 1 to verify / monitor or analyze a communication network 2 , In particular, in the case shown, it is a device according to the invention 1 for monitoring an industrial process plant. The communication network 2 consists of a process control center 3 and a bus system 4 , via which a multiplicity of participants (field devices / actuators 5 ) with the process control center 3 communicated.

The tester 9 detected in a desired state of the communication network 2 at defined measuring points of the communication network 2 in the 1 are marked with an 'X', in each case at least one measuring point-specific bus signal and / or at least one analog measured value signal. Marked measuring points X in the case shown concern the segment couplers 10 and several field devices / actuators 5 , The detected measuring point-specific bus signals and / or the analog measured value signals are used as desired data in a memory unit 6 stored. The form in which the data is preferably stored, for example in a database, has already been described in detail in the preceding section. Of course, it is also possible to take the nominal data and the tolerable limit values for the nominal data from the data sheets of the manufacturers of the individual components. In such a case, the follow-up measurement already serves a review and error analysis of the process plant. In particular, in this way, general disturbing influences on the process plant during operation can be clearly recognized.

At a later time in operation or in a defined actual state of the communication network 2 captures the tester 9 again the previously detected measuring point specific bus signals and / or the analog measured value signals and stores these values as actual data also in the memory unit 6 from. The storage unit 6 can eg be part of a data logger 11 be. The evaluation unit 8th recognizes a deviation or a trend deviation of the actual data from the target data based on a comparison of the actual data with the desired data. As soon as the deviation leaves a specified tolerance range, an error message is output. Also, the operator receives information if the error is still within the specified tolerance limits, but if since the last review a tendential increase in the error has occurred. The display preferably takes place on the display unit 7 ,

In 2 is a flowchart for visualizing the inventive method in the initial start-up or when restarting the communication network 2 to see. The individual process steps are described below, wherein the individual process steps are traversed in the indicated direction of the arrow.

First, the system-specific or measuring point-specific parameters and setpoint data are recorded. Either the acquisition is based on a measurement, or the information is obtained from the data sheets of the manufacturer of the equipment or devices. These target data are stored together with the specified tolerance values in a database, for example in the IBA tool. If the target data and the tolerance values, for example, are recorded and stored from the data sheets, an actual data acquisition is preferably subsequently carried out during operation of the process plant. The corresponding measuring point specific actual data become also stored in the database. This is followed by a comparison of the actual data with the desired data. This comparison is preferably carried out via an evaluation tool, but the evaluation can also be carried out manually. The deviations allow errors in the process plant or on individual field devices / actuators 5 recognize and correct.

This is followed by another actual data acquisition. These data are also stored in the database. The presence of actual data obtained at different times becomes a history of the communication network 2 created. On the basis of the data, a documentation can be made below and a reliable statement regarding the reliability of the process plant or of individual field devices / actuators 5 the process plant are taken. For example, a clear statement can be made as to which devices are very susceptible to faults and which work without problems.

In 3 is a flowchart for visualizing the inventive method in the recurrent review of the communication network 2 shown. The actual data is sent to all defined measuring points X of the communication network 2 detected. The recorded actual data is stored in a suitable database. This actual data is compared with the existing target data. If deviations between the actual data and the setpoint data that are located outside predetermined tolerance values occur or if errors that arise as a result of the history appear, these are remedied or suitable countermeasures are proposed and initiated. Subsequently, the actual data are recorded again and stored in the database. Again, a documentation is created and / or the results are printed out.

1

Device according to the invention

2

Communication network

3

process control system

4

bus system

5

Felgerät / actuator

6

storage unit

7

display unit

8th

evaluation

9

tester

10

segment

11

data logger

12

Network line

13

connecting line

Claims (11)

Device for checking / monitoring or analyzing a communication network ( 2 ), consisting of at least one control center ( 3 ), at least one bus system ( 4 ) and several components ( 5 ), which are sent via the bus system ( 4 ) with the control center ( 3 ), wherein at least one test device ( 9 ) is provided, which in a desired state of the communication network ( 1 ) at defined measuring points (X) of the communication network ( 2 ) in each case at least one measuring point-specific bus signal and / or at least one analog measured value signal is detected, a memory unit ( 6 ), in which the detected measuring point-specific bus signals and / or the analog measured value signals are stored as desired data; the test equipment ( 9 ) at a later time in an actual state of the communication network ( 2 ) detects the corresponding measuring point-specific bus signals and / or the analog measured value signals and stores and / or provides them as actual data, and wherein a display unit ( 7 ) is provided, via which a deviation or a tendency deviation between the actual data and the target data or error or impending error is communicated to the service staff or communicated. Apparatus according to claim 1, wherein an evaluation unit ( 8th ) is provided which, based on a deviation or on the basis of a tendency to deviate the actual data from the desired data, errors or impending errors in the communication network ( 2 ) detects and displays. Apparatus according to claim 1 or 2, wherein a data logger ( 11 ) is provided, which records the actual data. Apparatus according to claim 1 or 2, wherein it is at the control center ( 3 ) about a server and the participants ( 5 ) is about PCs. Apparatus according to claim 1 or 2, wherein it is at the control center ( 3 ) to a process control system and to the participants for field devices ( 5 ) for determining and / or monitoring a physical or chemical process variable and / or for actuators ( 5 ). Device according to claim 4 or 5, wherein several PCs or field devices ( 5 ) in a network thread ( 12 ) are arranged, wherein the network strand ( 12 ) from a network switch and several PCs or from a segment coupler ( 10 ) and several field devices and / or actuators ( 5 ) consists. Apparatus according to claim 6, wherein the PCs or the field devices and / or actuators ( 5 ) in a network thread ( 12 ) are electrically wired together or communicate wirelessly with each other. Device according to one or more of the preceding Claims, wherein the bus signals are electrical quantities and / or to bus or communication protocols is. Device according to 1 or 2, wherein it is in the evaluation unit ( 8th ) and / or the display unit ( 7 ) is a software tool. Device according to claim 1, wherein the test device ( 9 ) is a measuring device for detecting an electrical variable or measuring device for detecting communication-typical bus signals. Method for checking / monitoring or analyzing a communication network, comprising at least one process control center, at least one fieldbus system ( 4 ) and several field devices ( 5 ) for determining and / or monitoring a physical or chemical process variable and / or actuators ( 5 ) via the fieldbus system ( 4 ) with the process control center ( 3 ) communicate directly or indirectly, wherein in a desired state of the communication network ( 2 ) at defined measuring points (X) of the communication network ( 2 ) in each case at least one measuring point-specific bus signal and / or an analog measured value signal is determined, wherein the specific measuring point specific bus signals and / or the analog measured value signals are stored as nominal data, wherein at a later time in an actual state of the communication network ( 2 ) the corresponding measuring point specific bus signals and / or the analog measured value signals are recorded and stored as actual data and / or provided, wherein a deviation or a tendency deviation between the actual data and the desired data is determined and wherein the deviation or the tending deviation from the analysis of the communication network ( 2 ) is used.