DE2926419C2 - Device for recording electrical signals corresponding to random disturbances - Google Patents

Description

characterized in that
a recording device (50) which records on floppy disk is connected to the output of the delay device (43) and that the recording operation of the recording device (50) is only started when the input signals indicate a fault that has occurred.

2. Device according to claim I, characterized in that that the recording device (50) has a processing circuit (52) for processing the delayed Signal according to a data compression program contains js

3. Apparatus according to claim 2, characterized in that the processing circuit (52) a Encoding stage (57) and a time marking stage (53, 54) contains

4. Apparatus according to claim 1, characterized in that between the output of the Aufzeiciinungsgerätes (50) and the input of the demultiplexer (17) a digital / analog converter (44) is inserted is.

5. Device according to one of the preceding claims, characterized in that the paper strip writer (25) is designed to be removable and portable.

6. Device according to one of the preceding claims, characterized in that the paper strip writer (25) is recorded on ultraviolet sensitive paper using a cathode ray tube.

55

The invention relates to a device according to the preamble of claim 1.

Such devices, generally known as fault t> o Schreiber are designated, are in various versions from the magazine etz-b, Vol. 27 (1975) Issue 18, pages 482-484 known. In particular, they are used to record random faults that In industrial systems such as electrical power distribution networks.

Monitoring is of fundamental importance, especially in electrical power distribution networks. Everyone Incident, e.g. B. a fluctuation in the electrical Voltage, such as an overvoltage or undervoltage, which continues until the complete interruption of the Power distribution makes it necessary that a full analysis of the phenomenon can be done later to track down the causes of the disorder to make and take preventive measures.

These causes are very different and can involve accidental damage to the distribution lines or the latter associated elements are connected (switch, disconnector): they can be caused by undesired Contacts or short circuits are caused which occur briefly in certain parts of the lines. When it comes to overhead lines that are usually supported by masts, there is a frequent one Cause of disturbances in atmospheric electrical discharges, e.g. B. Lightning strike.

In all cases, the control of such disturbances, which cannot be foreseen, requires a permanent one Monitoring and the ability to investigate any phenomenon later. Hence the need arises for the use of recording equipment. In such recording devices, an information carrier is used which is designed in the form of a movable belt or strip and on which the variables to be monitored are recorded, in the form of either visible signals directly or after appropriate processing. In most cases this is the backing material Paper easily accessible for direct visual inspection, easily later with additional lettering can be provided and is suitable for archiving in the form of files.

The recording is usually done by ink or - more rarely - by photographic equipment, further processing may then be necessary.

The continuous record of those to be monitored However, sizes leads to an undesirably high paper consumption, because the incidents rarely occur and randomly on; to reduce the required amount of recording / recording material has already been suggested that the recording should only be made if a fault occurs.

This "triggered" mode of operation is caused by the occurrence of the fault itself, with the recording device rests between two disturbances. To precisely determine the causes of malfunctions should However, not only must the entire malfunction be known, but also the stable state immediately before it the incident.

Thus, during the occurrence of an incident, the recording device has to start recording begin before the disturbed signal reaches it, and this requirement can only be met by an item intermediate business being that has a delay between the point in time when the signal corresponding to the fault triggers the recording device, and the point in time when the recording itself begins. This element fulfills a function which is referred to in the following as that of a pre-release memory.

Certain known recording devices which record on paper are mechanical Pre-release memory provided. He is z. B. designed as a rotating intermediate carrier of cylindrical shape, on which the last seconds of the

recorded and then deleted. The transfer to the usually immobile paper tape by touching it takes place only with one Incident. The pre-release storage is thus determined by the value of the angular displacement between the Recording points and the contact points between the rotating cylinder and the paper shown.

In other recording devices that record on a paper tape, the pre-release memory is realized in electrical form as a digital shift register arrangement. The analog value to be monitored is converted into a digital quantity beforehand, is then delayed and mn output again into an analogue Size uingcsct / .i. to finally get on the paper tape to be recorded.

If there-; low resolution and low precision when recording on paper in real lines can be accepted, a sufficient evaluation of these fault records can be carried out, if the paper supply is constantly monitored and care is taken that the record is below good conditions.

In many other cases, however, these conditions are unsatisfactory. Because of their special characteristic properties, the disturbed electrical signals that often occur in distant and inaccessible places on the network, because of their extensive frequency band, not via ordinary electrical lines to a central one Measuring station are brought up, where the recording devices are easily grouped, monitored and serviced could become. One difficulty in using such devices is their Dispersion over places, often because remote from one another, to which there is access for the purpose of removal the recording medium or, if necessary, the replacement of the same only at very long time intervals is possible.

In order to reduce paper consumption, a low throughput speed must be selected, which results in a low resolution and makes the evaluation of the results more difficult; an examination with a magnifying glass is therefore necessary. The overall capacity of System ¹ : is usually limited by the size of the roll of paper.

If a malfunction of the recording apparatus occurs, then further left no trace of the to be tested Slörun _t · whereby the reliability and monitoring at remote locations, debilitating! will.

I'm achieving better reliability already proposed to replace the paper recording with a recording on magnetic media, and / was analog or digital on tape cassettes.

However, the order of magnitude of the data to be recorded is the digital input and output speed of a cassette, which reduces the storage efficiency! of information is restricted per second, especially if several inbound branches / ti monitor are. Cassettes are also sensitive, and the frequent changing of cassettes is remote Styles difficult. In addition, remaining! no material graphical record that .in place a direct visual inspection. Evaluation and appropriate description would be accessible. This The latter defect is also objectionable when the magnetic information carrier is a floppy disk

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(floppy disc), but with a much larger throughput.

The object of the invention is the recording device of the type specified in the preamble of claim 1 so that they have the advantages of the magnetic information carrier in the form of a floppy disk and that of a paper strip with each other united. This object is achieved by the characterizing features of claim 1.

According to the invention, then, there is the known paper hoop writer completely retained, and an essential feature is that between two Outlining this system another recording device is inserted, which is based on a magnetic Records the type of diskette or floppy disc.

The floppy disk and the paper strip thus form a combination that pursues a common goal, namely, on the one hand, storage with a high capacity and high resolution of a large amount of information that is not directly accessible, and on the other hand, enabling a direct visual examination for evaluation. So the common goal is that reliability and precision; jn is improved in the detection of the faults that have occurred.

According to a particular embodiment of the system, the paper tape recorder is always at rest and is only started under supervision if inspections are carried out at regular intervals, with any desired portion of the record readily available for instant visualization on the floppy disk is.

Because of the choice and direct supervision by the staff, a good record is made on the paper strip, at a higher paper speed, to achieve a better resolution to reach.

According to a particularly advantageous embodiment, the paper tape recorder is not constantly on Installed on the spot, but is carried along by the monitoring staff, with a single one Writer can serve for several remote locations. For this mode of operation made possible by the invention In most cases, the facilities are already in place in the fixed part of the system that for the extraction, processing and recording of the information stored on diskette on the paper strip required are. This allows the tape recorder to be used as an easily portable device with less Weight to be trained.

According to a further embodiment, the paper is a recorder Arranged in a central location, with all the technical facilities for high quality Recording; the floppy disk loaded on the spot with information then becomes a by the user Auslesegeriit for such plates brought to the this same central point is located.

In this embodiment, the user has Iiη spot does not have means of permanent Writing out the stored information. The weight to be transported, namely the diskette, is but then very little compared to the writer that was carried along in the embodiment described above will.

As a result of the invention, a secondary recording on paper starting from a primary recording is made possible on magnetic disk or floppy disk,

which avoided the limitations of direct recording on paper according to the prior art is subject to, namely a low resolution and / or a high paper consumption and / or a low reliability. So every incident or incident can be written on paper with a large scale and high resolution and this task can be performed by known recording devices. / .. B. ink pens, to be met.

According to a preferred embodiment of the invention, a special paper tape recorder is used used, the one with inscription by ultraviolet radiation on a sensitive to this radiation Based on paper, with the labeling by the moving triangle of an oscilloscope with a cathode ray tube r » he follows. Particularly in the case of the embodiment mentioned in the second place above, the resulting crgeueiiuc Lcichiiicii and simplicity of the paper strip Schreiber's advantage.

This device also allows all of them to be recorded in addition to the creation of an analog diagram required alphanumeric identity information that is available on the floppy disk (recording location, Date, hour, etc.).

It is also particularly expedient to insert a γ recording device on diskette, in which the recording takes place in digital form, in connection with a digital pre-release memory which is inserted either at the output of this recording device or at its input. jo

The intermediate recording on floppy disk allows a considerable improvement in the reliability of the System, because floppy disk recorders are essentially electronic in nature Have power consumption and contain only a small number of mechanical elements are at rest between two faults in the monitoring function.

After the transfer to the paper strip, there are two documents, which provides an additional guarantee function in terms of damage or loss is given. Using a floppy disk as a buffer, all the advantages of data recording are also available for studying random disturbances given in digital form, especially the search for disturbances, which by their characteristics are defined, the comparison of recordings of the same faults from different monitoring points, the possibility of using data compression, appropriate for the type of disorder, etc.

The invention will now be based on an embodiment. example and with reference to the drawing described. In the drawing, F i g. 1 a known recording device: and Fig. 2 shows a recording device according to the invention.

The in F i g. The known recording device shown in FIG. 1 includes an input stage 11 for adaptation the electrical signals or quantities to be recorded from a plurality of input circuits 4, 5, w 6, ... 12, a multiplexer 7, which is connected to the outputs 8,9, 10 of the input stage 11 is connected to a delay device 21, a demultiplexer 17 which is connected to the multiplexer 7 via a line 20 and as the last stage a paper tape recorder 25 with b5 Signal inputs 18 which are connected to the outputs of the demultiplexer 17.

The known recording apparatus also includes a connection 30, / wipe your output of the Multiplexors 7 and the input of a recording * - control circuit 32, which the Papicrstrcilensehreibci 25 controls. Furthermore, a Zcitsiempclschluss 41 is a cm Connected to / calibration input 70 of recorder 25.

This device works as follows: The electrical signals or quantities corresponding to the data that correspond to the uiif / uzcii'lincnding are sent to the input terminals I, 2, 3 clci ¹ input circuit :: !! 4, 5. 6. ... 12 created. / ur adjustment of the level. DurchlaUbaiules etc.

At the output of the first stage the signals .in the input terminals, 9, 10 of the multiplexer 7 «nj ·«. ·· lays. The task of this multiplexer 7 is then to scan all signals cyclically one after the other in order to send these variables to a single output output 13 respectively.

Ate this connection · «·. dip connection 30 unconditional sen. Connection 30 triggers the appearance of a signal to be recorded via the recording control circuit 32 commissioning the recorder 25. That to the input 29 of the delay device 21 applied signal experiences a delay that behind the demultiplexer 17 ensures that in the Desired way this signal is applied to the signal inputs J8 of the recorder 25 only after the Paf Icristcifcn is in motion.

The design of the delay stage 21 is determined by the fact that it is simpler. a clever one Signal in digital form ils to delay in analog form. Therefore, according to the prior art, it contains the delay stage 21 is an analog / digital unit network 42, a delay circuit. which is designed as a shift register 43 and a digital / analog Unisetz.er44.

The shortcomings of such a recording device have already been explained at the beginning; they surrender from the limited resolution of the real-time records made on paper. A variation this arrangement, which would consist in briefly inputting the signal into a semiconductor memory and then made visible on paper with a higher resolution would either become a very large memories lead and / or limit the duration of the disturbances that are recorded can.

F i g. 2 shows an embodiment of the invention Recording device. In this figure, the elements similar to those in FIG. 1 correspond with denotes the same reference numerals.

The embodiment according to FIG. 2 is characterized in that in the delay stage 21 a recording device 50 is inserted, which records on magnetic disk or floppy disk (floppy disc).

The operation of this device is as follows: The Signals to be recorded are applied in analog form to inputs 1, 2, 3, and multiplexed in multiplexer 7 and brought into digital form in the converter stage 42. Then they become out of the already detailed for the above reasons, in a semiconductor memory circuit 43, and in the floppy disk recorder 50 entered. This device 50 includes a drive 51 and associated processing circuitry 52 for the processing of the "to be recorded signals and a control circuit 58 for Control of the recording.

At the output of the recording device 50, the signal as in the known device according to FIG

to a digital / analog converter 44. a demultiplexer 17 and a paper tire writer 25 applied.

In a certifying step 5, the verifi cation> rsschalluiigeii 52 fulfill a "/ urgent temp. which is controlled by an external signal generator 54 via a synchronization lending system. The real line counter also supplies the trigger signals for the output scanning via line 55. The processing circuits 52 also process the digital signals in the block denoted by 5f> and perform the function in a signal 57. that the words are brought into shape and identification and date codes are inserted. According to a further development, this processing includes a compression program for the signals to be recorded depending on their significant fluctuations with the aim that no stationary data are transferred to the disk and consequently only the required information is stored in a minimal volume. The file compression program according to the invention is as follows:

At the output of each sampling cycle carried out by the multiplexer 7, the processing ¹ compares, circuitry, the won currently stored in each channel with that stored in the corresponding channel during a previous cycle and, depending on the discrepancies found, the circuit decides whether the recording of the new sample should be made or not.

This · * decision applies to all of the input channels depending on the fluctuations of all cannulas: there is only no recording if if all cannulas remain very close to the values that are used as a puller.

Restricted for security reasons! the processing auxiliary circuit the number of eliminated samples on citicn vm'besiifnFfiiC-n Wori.

the recorded scan is preceded by a <or which indicates the number of samples eliminated since the last recording.

The sampling used at the point in time / as a reference value for the comparison can be that which was carried out at a point in time '/ -I) when the idle state of the monitored lines is completely unknown; when there is normally a periodic signal with a known period T on the lines. so the reference value can be the sampling that was carried out at time (tT) .

The tolerances in the comparison process and the limit on the number of samples eliminated are set depending on the application of the recording apparatus itself.

The visualization of the data can easily take place in the manner described by the fact that a digital / Analog Unisetzer 44 is used to which a demultiplexer 17 follows, which is synchronized via a line 20 with the multiplexer 7 and to the paper tape recorder 25 is connected.

When the paper tire recorder / ur record of data in digital form is suitable. so the filling bids a diskette recorder the other Advantage that on the paper strip except for the Analog data corresponding to signals also provides data on the date, technical conditions, etc. directly can be recorded in alphanumeric form in any desired type coding. This possibility exists in particular in the case of recording devices with a cathode ray tube, in which

the recording is made on ultraviolet-sensitive paper.

For comparison of the recording device according to the invention with a state-of-the-art technology, the following values were determined:

With a typical paper speed of 20 cm / s, a normal paper roll enables JO m length according to the state of the art, the recording of disturbances with a maximum duration of 150 s a given resolution; with insertion of a disk storage device the maximum total duration is 400 s without data compression and 700 s with data compression.

By slowing down the readout from the floppy disk while recording on the paper strip furthermore, the expansion of the time scale on the paper strip allows an increase in the resolution by a factor of 5 to 10, with the paper consumption remaining low, far only those faults are selected that are considered important.

For this purpose 2 sheets of drawings

Claims (1)

Patent claims: 1. Device for recording electrical signals corresponding to randomly occurring disturbances, by a paper tape recorder (25) with - Input circuits (4,5,6 .... 12) for processing the input signals applied to their inputs (1, 2, 3, ...), - a multiplexer (7) which cyclically scans the outputs of the input circuits (4,5,6, ... 12), - An analog / digital converter (42), which converts the output signal of the multiplexer (7) into a digital signal implements. - a delay device delaying the digital signal (43), - A demultiplexer (17) which sends the delayed signal to the inputs of the paper tape recorder demultiplexed,