DE3213155A1 - Method for the monitoring of a compressed air generating system and device for carrying out the method - Google Patents

Abstract

A method and a device for monitoring a compressed air generating system comprising at least one compressor and one compressed air dryer is described, which has measuring sensors for recording operating data of the compressor and the dryer, such as pressure and temperature of compressed air, ambient air, cooling water and the like, and display devices for such operating data, at least some of the monitored operating data (for example number of operating hours between two filter changes, and also extreme values of pressure and temperature etc. attained) being, according to the invention, electronically stored and, on demand, represented on the display devices. A programmable microprocessor is preferably used in order to combine the variation in time of certain operating data with predetermined time functions and/or with the variation in time or with values at certain points in time and to emit different signals for the display devices according to the result of the connection.

Description

^: . ^:: - "- ■■ ^: ν." - 321315 !:

. Ernst Stratmann

PATENT ADVOCATE
D-4OOO DÜSSELDORF 1 SCHADOWPLATZ 9

VNR; 109126

Düsseldorf, April 6, 8213 ■

VIA Gesellschaft für Verfahrenstechnik mbH 4000 Düsseldorf 1

Method for monitoring a compressed air generation system and device for carrying out the method

The invention relates to a method (working method) for monitoring of at least one compressor and one compressed air dryer Comprehensive compressed air generation system, the sensors for recording operating data of the compressor and the dryer such as pressure and temperature of compressed air, ambient air, cooling water and the like, as well as display devices for such operating data.

Because of the loud noise generated by compressed air pressure compressors it is common to use at least the compressor of a compressed air generation system to be arranged in an area where operators are usually not available. For convenience You will often also see the other parts of such a compressed air generation system, in particular the compressed air dryer, at the Place the compressor if the compressed air generation system is not designed as a compact unit anyway. This means that the essential parts of the compressed air generation system are not under constant direct observation by supervision staff stand. After all, it was previously possible and customary to view the various operating data of the compressed air generation system, such as, in particular, the pressure and temperature of the compressed air generated,

BAD ORIGINAL ' _cop y

Humidity and temperature of the ambient air, temperature of the To detect cooling water and the like with the help of sensors and to supply appropriate display devices so that the operating personnel was able to determine the current status of the operating data if necessary, at least a random sample to ensure monitoring.

Depending on the value of the plant, therefore, up to now more ^ or less regular intervals an operator-the display devices inspect the operating data displayed with it known or displayed on the measuring devices Compare par value data.

It has also been common up to now for larger excesses to operate certain operating data alarm devices, which either call an operator or the Plant shut down as a whole or in certain parts so that major damage is avoided as far as possible.

These previously practiced procedures have the disadvantage that they are relatively labor-intensive and, moreover, cannot prevent longer shutdowns in the event of malfunctions comes, especially when the normally available operating personnel is responsible for the actual maintenance of the system not carried out, but specialists have to be called in for it. Until these specially trained maintenance specialists Having made the system ready for operation again, a long time may elapse if such malfunctions occur more frequently can make the entire arrangement uneconomical.

The object of the invention is to create a method for monitoring a compressed air generation system of the type described Type in which these disadvantages are avoided and that enables the monitoring and maintenance and possibly also control of the compressed air generation system to simplify significantly and thus to make it cheaper.

■ - * · - ■ "" ■ ^: ■ 321315

The object is achieved in that at least some of the monitored Operating data, such as the number of operating hours between two filter changes, reached an extreme value of pressure, temperature, humidity and the like, electronically stored and on request on the display devices being represented.

According to a further development of this method, in which a programmable microprocessor is provided, the Course of certain operating data with predetermined time functions and / or with the course over time or with values to be determined Linked points in time and depending on the result of the link emitted different signals for the display devices

The electronic storage makes it possible to determine processes that were in the past and based on such data, for example, to determine the cause of the malfunction. If a programmable microprocessor is provided, the working process can be expanded so that e.g. not only certain extreme values or times can be monitored and saved, but rather the chronological sequence of certain operations data. This course over time is of particular importance in such compressed air systems, as it provides important information for Causes of faults, especially experienced maintenance personnel In the event that experienced maintenance personnel do not immediately or should not or cannot be used in every case, the programming can also be carried out in such a way that this Time course of certain operating data is compared with stored predetermined time functions and in the event of deviations corresponding display or alarm signals are given or it is also displayed directly what kind of malfunction is present. The temporal course of certain operating data can, however, instead be compared with the temporal course of other operating data or at least linked to operating values at a certain point in time in such a way that it can be determined whether the operating data and / or their chronological sequence match correctly or whether the link leads to values,

BAD ORIGINA! - COPY

which must not occur during normal operation. In the latter case, the possibility would again be given to activate appropriate alarm or display devices. Since the possibility of Speichhrung is given such operating data, operating data histories and linking results _f it is relatively easy with this procedure, either to control signaling devices in such a way that even inexperienced maintenance staff is immediately informed of the correct or nearest cause of the fault, or that an expert maintenance by checking the lights a diagnosis of the cause of the error, the previous operating sequence and the like can be identified either clearly or with a very high degree of probability.

In this way, a compressed air generation system can be used without any disadvantage can be operated completely without monitoring or operating personnel. That in this way a build-up of experience about Störungsbzw. Failure causes and failure factors are not possible, is according to the invention of no disadvantage, since the invention Procedure to determine the causes of malfunctions and failures enables.

The procedure according to the invention also prevents unnecessary long downtimes, as the cause of the fault can be determined much more easily and quickly can, so that in particular small faults can be resolved quickly and without problems. This also has the advantage that such minor disturbances do not exist for a long time which could otherwise lead to major failures.

It is peculiar to unguarded compressed air generation systems that occurring malfunctions only affect the production and process sequences supplied by the compressed air generation system be noticed. This can result in high operating costs as a result of degraded quality, decreased production or even shutdown of production units or the entire system may occur. It does not matter whether the compressed air generator station as a central generating station for the energy

* - ■ '- ■■ "■■' ^: 321315

carrier compressed air is used, or whether instead of a main station If several individual stations are installed in the company, the method according to the invention is for both arrangements decisive advantage.

In the event of a malfunction, for example, a- ~ A maintenance man who is usually not a specialist in the repair and maintenance of the compressed air generation system The task is to diagnose the cause of the failure. In many cases, however, are due to the passage of time between Failure and arrival of the maintenance man are the causes of the failure no longer or no longer fully recognizable. In addition, the maintenance man is often due to a lack of experience unable to make a truly accurate failure diagnosis. If he meets a partial or z. B. also quite correct Diagnosis, he usually lacks the experience of how the error can be eliminated or at least the occurrence of more extensive ones Damage can be avoided »This leads to the fact that the initially only possible minor damage increases in size that finally external specialists have to be called, which with considerable time delays and also additional ones Costs associated with it.

Compressed air generation systems of the type mentioned above are also not only subject to initial commissioning, but mostly also a variety of recommissioning, z. B. due to of shift work or weekend shutdowns. Here, too, it must be assumed that the often quite extensive operations individual control parts on the compressed air generation system may not be carried out properly, resulting in damage to the system and subsequent malfunctions occur in the compressed air network.

All of these problems can be solved relatively easily by the method according to the invention given above.

ΓΠΡΥ BAD ORIGINAL ^

The invention also relates to a device for carrying out the method, which preferably also includes a microprocessor comprises, wherein the microprocessor has a comparison arrangement for Comparison of the individual operating data with stored setpoints and a downstream link arrangement for linking the size of the deviations, a clock device for determining the chronological order of the occurrence of the deviations in the operating data and a time function memory has, to which the chronological order of occurrence of the operating data deviations are supplied and which are exceeded when A corresponding display of the specified setpoints supplies the display devices. This results in an electronic one Monitoring, diagnosis and possibly also control device, which all the links resulting from the operating conditions of the individual parts of the compressed air generation system (compressor, processing device, environmental conditions) may contain so that these conditions by comparison with corresponding measured data for their compliance can be monitored.

The programmability of the system not only monitors compliance with individual physical variables, but also also all possible combinations of deviations with regard to the size of the deviation and the order in which it occurs, as well as at the same time compared with a typical behavioral being. This then forms the basis on which not only the monitoring and if necessary control takes place (e.g. sequence sequence), but this also forms the basis for an automatic diagnosis of the cause of the fault.

This enables an early warning in the event of a negative trend with a simultaneous indication of necessary interventions, see above that existing, possibly not particularly qualified personnel can carry out these interventions. Also is after Failure of the system an automatic diagnosis of the cause regardless of the presence of a specially trained specialist

* · "■" ■ · "■ - ■ ^: - - ^ - 321315 - 11 -

man's possible. Finally, a diagnosis code can be implemented / which clearly refers to the instructions given in a repair manual to enable targeted elimination the cause of the fault and, if necessary, repair the system]

Various safety devices can also be installed in install the possibly existing control system in such a way that in the event of serious malfunctions the arriving specialist staff additional information on the historical process and the extent of the failures are given. At the same time a Provide a type of self-protection so that unauthorized intervention by unqualified personnel is made more difficult or a such unauthorized intervention was recorded indelibly so that any warranty cases can be clarified more easily,

The invention is explained in more detail below with reference to exemplary embodiments which are shown in the drawings.

It shows:

1 shows a schematic representation of a compressed air generation system conventional design equipped with the monitoring device according to the invention is;

2 shows a schematic detailed illustration of a particularly favorable embodiment of the monitoring device according to the invention;

3 shows a suitable one for receiving the monitoring device Housing in a plan view, a view from the right and a view from the front, wherein the Top view of the display and operating elements in Shows shape and arrangement;

Fig. 4 shows another embodiment of the front panel with the associated operating and display elements;

BAD ORIGINAL COPY

Figures 5, 5a

yet another, simplified embodiment of the Front panel;

Figures 6 and 7

two examples of the key assignment of the control keypad, which can be seen in the embodiments of the front panel of FIGS. 3 and 4; - -

Figures 8a, 8b

a tabular list of display options with three groups of seven-segment light-emitting Diodes;

Figures 9a, b and c

a flow chart to explain the operation of the monitoring device according to the invention; ■

Figures 10, 11 and 12

three further flow charts to explain the operation; and

13 is a table showing the possibilities for two-digit error coding.

In Fig. 1, a compressed air generation system 10 is shown schematically, the compressed air for a number of consumer systems 12 supplies, for example, manufacturing or processing equipment 18, which require compressed air as an energy source. The compressed air generation system comprises, as shown in FIG. 1, a compressor 14, which in a conventional manner, for example driven by an electric motor, air sucked in from the environment, see arrow 16, compressed and via a pressure line 18 a compressed air dryer 20, which dryer 20 not only brings the compressed air to a desired temperature, if necessary, preferably dissipates the heat generated during the compression process, but also entrained oil mist and condensation

* - ■ """■■;■" ^: "'321315

sation moisture is extracted from the compressed air and this condenses Liquid discharges via a condensate drain 22, for example. There may be other components, which are not shown here. A line 24 is then compressed air of the prescribed pressure and with the necessary quality in terms of dehumidification, dedusting and oil removal to a distribution pipeline 26 which the individual stations 18 of the consumer system 12 with ^ compressed air provided. Via sensors 30 at various measuring points within the compressor, dryer and condensate drain as well as within the room in which the individual elements of the compressed air generation system 10 are set up, the Operating data to be monitored recorded and via lines 32, 34, 36 and 38 of an electronically operating monitoring device 40 supplied, which picks up these signals and compares or links them with stored values and based on this Comparison or linking process generates control signals which are supplied to display devices 42 on the one hand and to the other on the one hand and above but also via lines 44, 46 and 48 to individual elements 14, 20, 22 of the compressed air generation system 10, if these elements are controlled in any way should be.

2 shows the monitoring device 40 according to the invention in one embodiment in a more detailed schematic representation form, which also includes a microprocessor 50. As can be seen, the monitoring device comprises a data busbar to which various blocks are connected, in addition to the already mentioned microprocessor 50, the sensors 30, the display devices and possibly controls 42 and memory devices of various types, such as programmable memories with fixed content 52, non-programmable memories with fixed content 54 and memory devices 56 in which both as can also be read out again. The arrangement of FIG. 2 represents a programmable logic controller as it does is known per se from numerous publications, see for example ETZ, Vol. 102 (1981), Issue 18. Such memory

BATH ORIGINAL

programmable controls can be made with the help of appropriate Program programming devices in such a way that they are necessary for the particular system to be controlled or monitored Signals processed in the appropriate manner and the associated control signals generated.

An embodiment of a special in the present case a suitable program will be explained in more detail later.

The necessary for setting up the monitoring system Electronic components are relatively small and can therefore be accommodated in a housing whose size is the maximum the size of a suitcase, but can usually be kept much smaller.

Fig. 3 shows such a housing design in a plan view, a view from the right and a view from the front, the housing, for example, from a base part or front panel 60 and a deep-drawn cover 62, the connection options for input and output lines 64,

66 and a front panel cutout 68, the size of which is approximately 10 × 20 cm, for example, and which has a keypad 70 made up of 4 × 4 pushbuttons 72, for example. In addition, a display panel 74 to recognize the letters, numbers and other characters forming light emitting segments is formed, also still indicator lights 78 are provided which are in connection with certain terms such as "Time", ^"0 C" (temperature), " bar "(pressure), start, operation, trap, filter change.

The inputs 6 4 and outputs 66 are preferably arranged in the form of plug strips, but other connecting devices are also conceivable.

Fig. 4 shows a front panel section similar to that of Fig. 3, while Fig. 5 or 5a shows a front panel, by omitting the keypad 68 and some of the luminous

'·· ■' · ■ "■ '· - " ■ ·; 321315

diode elements 76 simplified and in particular for a Monitoring device is intended that is not programmable Processor, so that the program input can be omitted via a keypad.

As can be seen from FIG. 4, the keypad 70 has, on the one hand, the number keys 1 to 9 and 0, as well as others Keys that are used to enter commands, such as the start / stop key, the pause key, the time key, the enter key for diagnosis, a key for displaying the pressure (P) and the temperature (T). The keys can also be designed as illuminated keys. In addition, as shown, there are special ones There are signal lamps that highlight certain operating states, for example the switch-on state, the start-up status (start), the status of the necessary filter change (Filter), the status of the switched-on condensate drain, whether or not a nominal pressure has been exceeded a limit temperature or just the fact that the values displayed by the numeric keypad relate to the print or get the temperature.

In the following, let us now consider a particularly advantageous exemplary embodiment for a monitoring device specifically designed for a compressed air generation system.

Output signals from five temperature sensors of the same type are generated (similar to the sensor 30) and the output signal of a Overpressure switch evaluated, which is triggered when a certain compressed air pressure is exceeded. The temperature sensors record the following temperatures:

t ₁ inlet temperature of the compressed air in the dryer 2 t ₃ cooling temperature, this is the temperature to which the compressed air is cooled,

ty ambient temperature of the dryer,
t _o evaporation temperature and

t _{c is} the condensation temperature, the latter being used to control a fan.

BAD ORIGINAL COPV

For all five temperature measurements, a measuring range of, for example, applies 0 to 70 ° with a certain measurement accuracy of, for example, 1 or 1.5 C.

These five measured temperatures are offset by corresponding maximum values to be observed, which can be set depending on the desired operating conditions, e.g. in the range from 30 to 70 ° C for t .., t _y and t _c (this maximum value is then identified with the index H in each case ), while the setting range from 0 to 30 ° C appears appropriate _{for the cooling temperature t 3} and for the evaporation temperature t _Q.

It is expedient to use the monitoring device to a certain extent for control purposes, in particular for controlling the condensate drainage, that is to say a valve that is opened to allow condensate liquid to flow out. In the embodiment described here, the monitoring device therefore has an output Q ^ for controlling the diverter valve. A second output Q ₂ is provided in order to control an external alarm transmitter 43 (see FIG. 1), for example a signal horn.

In the simplest form, the display devices 42 can have those of FIG. 5 or 5a, which consist of a display field 74 with a three-digit display made up of seven-segment light-emitting diodes to display temperatures with one digit after Comma (.) Shows. This resolution, which is high compared to the measurement accuracy, allows fine trend monitoring. This seven-segment Light-emitting diode displays can, for example, have a height of 13 mm. The other displays are light-emitting Diodes with a height of 5 mm and can have different colors, for example the color yellow for status displays and the color red, possibly flashing, for alarm displays. For example, the LED (light-emitting diode) labeled "Operation" (FIG. 5a) could have a yellow color and when switched on Compressed air dryers light up, e.g. B. to signal applied supply voltage. A yellow LED with the designation

"Trap, on" could be activated when the trap valve is open to shine. A red "Fault" LED could occur if an upper limit temperature is exceeded and if the overpressure switch is closed the flashing. A red LED labeled "overpressure" can be used (together with "Fault") flash when the overpressure switch is closed. Other yellow LEDs relate to the inlet temperature, Cooling temperature, ambient temperature, evaporation temperature or condensation temperature and could light up together with the number display to identify the temperature displayed.

As operating elements there are three buttons 72 on the front panel ( to recognize according to Fig. 5a, for example, have the following function «: button" arrester, one / hand "is used to check the Arrester function. Pressing it down opens the trap valve for the set duration of a few seconds, for example and thus enables the functionality to be checked.

The button "Acknowledgment, diagnosis" enables a shutdown of the external alarm device and the deactivation of the "Fault" LED after an alarm (acknowledgment of the alarm). Additionally can durvjh this key the upper limit of each displayed Temperature can be called up and thus serve as a diagnostic and setting aid.

The button "temperature display, retrieve" could be used to select the temperature to be displayed. A button (not shown here) for "filter change done" could also be provided to switch off a filter change indicator and restart a new filter change time interval.

It is now intended in detail the function of the embodiment of the invention shown in Fig. 5 or 5a with a front panel Monitoring device will be explained in more detail, this monitoring device being essentially on aligns the dryer 20 and can be switched on with this. Then the corresponding indicator lamp 78 "Operation" lights up. The above The five temperatures listed are measured continuously

BAD ORIGINAL _c0P y

and monitored with regard to exceeding the set upper limit values, but not displayed. After pressing the Press the "Call up" button, the inlet temperature appears on the numerical display 74. With each further depression of this key 72 the display changes in the cycle: inlet temperature, cooling temperature, ambient temperature, evaporation temperature, condensation temperature, Inlet temperature, etc., while the corresponding LED lights up to identify the displayed " Temperature up. By additionally pressing the button. "Acknowledgment, Diagnosis ", the limit value of the temperature displayed can be queried. To avoid errors about whether the Temperature or its limit value is displayed, the limit value is only displayed as long as the button is pressed. The temperature display goes out automatically a few minutes after the last press of the "Call" button.

When a temperature limit is reached or when the overpressure switch responds, an alarm is triggered, i. H. the LED "Fault" starts to flash and a possibly connected alarm device is switched on. At the same time, either the temperature triggering the alarm is displayed or the "overpressure" LED flashes. This display does not go out automatically, but only after pressing the "Acknowledgment, diagnosis" button, with which also the external alarm device is switched off. The simultaneous change of the display to the limit value as defined above allows an assessment of the disturbance. The other temperatures can then be queried as described above will. If such a malfunction occurs, further malfunctions are not registered, so in any case the information is retained via the triggering variable and is not overwritten by a subsequent fault. The malfunction function is only activated, for example, half a minute after switching on, in order to generate false alarms during the switching on process to prevent.

Furthermore, an alarm is triggered when a filter change is due, with a fixed time interval of several for the filter change

■ · ■ "*"'' 3213K ^C -

a hundred or a thousand hours can be provided. After this change interval has elapsed, an alarm device that may be connected is activated switched on and the "filter change" LED flashes. Pressing the "Acknowledge, Diagnosis" button only activates the alarm transmitter switched off while the "filter change" LED is switched off and the change interval is restarted, one here not shown key follows, which also z. B. can be attached to the back of the device, from where the filter change he follows. The filter change alarm is independent of the malfunction alarm specified above, so it does not block it.

The condensate drain control provided here includes the following functions: The drain valve is periodically short-term open, opening and closing times are by appropriate adjustable timers within the monitoring device adjustable (for example by means of a trimming potentiometer with scale accessible from the rear of the device). By With the "On / Hand" button, the valve can be opened by hand, it then remains in accordance with the set opening time opened. The "On" LED lights up for both manual and automatic opening.

The mechanical structure of the monitoring device is not critical For example, an acrylic glass front panel with a label and a faceplate would be beneficial is. The aperture pressure means that holes or cut-outs for the display are unnecessary. The housing can then be made from this Front plate (in Fig. 3 it can be plate 60) and a deep-drawn cover screwed on the rear.

With the shape of the front panel, it is beneficial to combine the operating and display elements according to the function groups, whereby the confirmation key belonging to a function group should be arranged at the lower edge so as not to have any when pressed To cover up the display. The arrangement of the smallest group (arrester) on the far left allows the display to be spatially separated "Operation". In addition, the arrangement is chosen so that sufficient

BAD ORIGINAL _C qpY

- There is enough space for the lettering.

The electronics including display and operating elements as well as external plug connections are mounted on a circuit board, for example a map of Europe. The digital part of the circuit is built in CMOS technology, which makes the use of a small nickel cadmium battery to maintain the Information about the number of operating hours between two filter changes is ensured even in the event of longer operating voltage failures.

Let us now look in more detail at a further embodiment of a monitoring device received, which has a microprocessor with working memory and program memory including ready-to-use User program as well as with peripheral assemblies for querying the inputs and the operating elements or for control which has outputs and display elements.

In order to be processable by the microprocessor, it is advantageous Amplifier for the evaluation and normalization of the output signals of the transducers provided, if necessary with Correction devices to compensate for systematic and control-related measurement errors. The amplifiers are then analog Measuring point switch connected downstream. The analog signals are then matched to the accuracy of the measurements Resolution converted into digital signals by analog-to-digital converters.

The display circuits are correspondingly provided with hardware or software driver devices, the operating elements with hardware or software decoding.

As in the case of the embodiment already described, there are certain Input signals provided in order to evaluate analog values can (pressure, temperature), while other signals to determine switch states (pressure switch, overload switch, Valve contacts).

The setting of the limit values of switches is done mechanically and is therefore independent of the electronic monitoring device. In contrast, the various limit values for the analog variables (in particular pressure, temperature) are set by the monitoring device defined, whereby there are different possibilities:

a) constant limit values that are the same for compressed air generation systems or compressed air dryers of different designs can be made available to read-only memory 54 (see FIG. 2) as constants.

b) Limits that apply to a specific device type, e.g. B. Compressed air dryer are typical can be set via the keyboard 70. Your value is protected by a numeric code, to prevent accidental or unauthorized changes.

c) Variable limit values can be adapted by the user to the needs of his system, although the setting range, if necessary, is restricted by constant limit values.

d) Program-controlled limit values; The program assigns them a value.

The embodiment of the microprocessor-controlled monitoring device can take a larger number of temperature measurements perform than was the case with the previously described embodiment: The following temperatures are measured:

t- inlet temperature
t ₂ outlet temperature
t ₃ cooling temperature
tQ-jT oil pan temperature
t _Q evaporation temperature
t _r condensation temperature

^ COOL ^Ku Coolant Temperature.

These temperature values relate specifically to the dryer and its operating conditions.

BAD ORIGtNAL COPY

In addition to the temperatures mentioned, the following pressure measurements are also taken:
P ₁ inlet pressure
P ₃ pressure drop (inlet pressure compared to outlet pressure), from which the outlet pressure P ₂ = P ₁ - P ₃ can be calculated by the microprocessor.

In addition, the following switch positions are evaluated by "corresponding signal inputs:
P _c overpressure (signal occurs when the switch is at a

certain overpressure of z. B. 24 bar remains closed) P _Q negative pressure (signal occurs when the overpressure switch is at a negative pressure of, for example, less than 3.8 bar

remains open)
s circuit breaker (signal occurs when the circuit breaker

opened when overcurrent)
In inlet valve contact
Out outlet valve contact
byp bypass valve contact (signal occurs when the associated valve is closed.

The monitoring device provides several outputs for control purposes:

Q ₁ to drive the refrigerant compressor relay, Q ₂ for driving the fan relay, Q ₃ for driving the Ableiterventils, Q. for driving an external alarm device and Q ₅ for switching the air compressor when this is to be switched on only in certain modes of operation, for example.

The microprocessor-controlled monitoring device has a specially designed light emitting diode display device, which is a particularly versatile and memorable and also of larger size Distance delivers conspicuous display. The display is built up from a line of a total of nine seven-segment LEDs, the first LED, for example, a height of 13 mm, the

- 23 - '■■ "-

next five a height of 7 now and the last three again can have a height of 13 mm, which enables Symbols / index names, equal signs and numerical values (either three-digit or two-digit with minus sign) for to display the individual measured values. FIGS. 8a and 8b give some exemplary embodiments for such displays. So the ad of temperatures of various kinds including associated indices, negative temperatures, the state of, switches including their designation, as well as the display of instructions for the operating personnel in the course of the start routine enables and thus eliminates the need for an LED for the pause display.

In addition to this display panel are shown in FIG. 4, which shows the front panel of the microprocessor-controlled monitoring device nor individual LED's are provided, the LED is ^"0 C", which lights up when the keypad indicating a temperature corresponding to the LED "bar", which lights up when a Pressure is displayed, the "Start" LED, which lights up while a start or restart routine is running.

In addition, there are again indicator lamps in the form of light-emitting ones Diodes provided, which indicate normal operation ("operation", also the opening time of the condensate trap ("trap") which lamp also lights up during the programming of the arrester times, as well as a lamp to display the case to change the filter ("filter change").

It is now closer to the controls of the erfindungsgernäße: Monitoring device received. An "On / Off" switch is not provided, rather the device works together with the monitored system, for example in particular the compressed air dryer switched on, especially since the monitoring device is expedient contains a program that starts automatically when the system is switched on and the temperature of the oil in the heated monitors the oil pan and issues a fault message, "if the oil pan nerve temperature has not reached the minimum value required to start the compressor within a specified time. To the

BATH ORIGINAL ^C ° ^P

Stopping the dryer (with the exception of the oil pan heater) is against it a stop button is provided, whereby a program for implementation is initiated, which will be discussed in more detail below will.

The only operating elements that remain are a button for clearing the filter change indicator on the back of the device (similar to as with the embodiment already described at the beginning) as well as a 4x4 membrane keyboard, which is accessible to the user Allocation from Fig. 6 emerges.

With this assignment, the following operation can be made possible in a clear manner (the names of the keys to be pressed are in quotation marks):

a) Start: After "Start", depending on the requirements, the start or Restart program initiated. Was the dryer over If the power switch is switched off, "Start" is not necessary after switching on. (The same applies to a power failure.) "Start" is only required if "Stop" has been pressed beforehand. (This requirement also applies to interim There is a power failure.)

b) Stop: After "Stop", an unlimited pause is initiated. "Stop" is also a prerequisite for deleting the filter change indicator using the button on the back of the device, d. H. , The user is required to switch off the dryer and open the dryer housing.

c) Break: After "Break", the last programmed break time appears in the form shown in Fig. 8b, the numerical value for example in the range of 1 hour = break - 99 hours can lie. At the same time, the pause time begins to count down, and the remaining time is displayed. During the Pause can set the pause time using the number keys and then "Enter" must be reprogrammed. "Start" cancels the pause.

d) Operating hours: According to "operating hours" becomes the total number of operating hours of the cooling compressor is displayed in five digits with the 7 mm LEDs.

e) Diagnosis: After "Diagnosis" all segments and light up Single LEDs. A self-test is carried out after approx. 2 s, the almost complete check of the main memory (RAM) and a sample check of the program memory (EPROt or later ROM). In the event of an alarm or an emergency stop, the LED and memory test are replaced by an error diagnosis.

f) Query of measured values and limit values: After pressing a symbol key "t" or "p" and a first index key "1, 2, 3, COOL, OIL, 0, C", the symbol, index, equal sign and current numerical value of the appear corresponding measured variable in the display. If a second index key "H" or "L" is then pressed, the index in the display is supplemented accordingly (with t _COOL the equal sign is overwritten) and the upper (H) or lower (L) limit value appears.

g) Change of limit values: Following the query of a limit value, this can be changed by pressing the corresponding number keys and then "Enter" can be changed. This possibility of change however, it is restricted to "variable" limit values as explained above.

h) Drain times: After pressing the "AbI." can alternate with the numeric keys opening and closing time span of the diverter valve (e.g. in seconds). The display shows as an indication of the time entered "Open" or "Closed", the "arrester" LED also lights up. The possible setting ranges are: open: 1 ... 10 s, close: 30 ... 600 s.

In addition to this key assignment that is valid for the user (Fig. 6), there is another key assignment that (only for the service technician) can be accessed by entering a numeric code beforehand. Fig. 7 shows the key assignment after entering this number ' codes which differ in a certain way from the keyboard layout of FIG. In particular, are different from those previously described Functions described in a) to d) are no longer available. The change of limit values is now based on the "type-specific

BATH ORIGINAL ^C ° ^P

see "Limit values expanded. In addition, the following additional ones are available Functions:

i) Query of measured values and limit values at different times before the last failure (emergency stop): The time is set using "Time" and a number key. The display shows the equal sign to indicate the point in time replaced by the entered number. "0" corresponds to the time of failure, "1" to a time of 0 ... 15 min before; all other points in time are further back in 15-minute steps. All queryable values are at least for four times stored, if the memory space permits, for z. B. up to ten points in time. The query of the values takes place as described above.

j) Querying the pressure switch: It is carried out in the same way as the other queries with "p ^H and" C "or" 0 ". The switch status is indicated in the display by" Hi "or" LO ".

k) Erase: After a failure with a start lock (which will be discussed later), the memory mentioned under i) and j) will not be used overwritten. After "Erase", this write lock and the start lock are canceled.

1) Query of the operating time since the last deletion: This is done with "Last.Lösch ^11. This enables you to check whether new attempts to start up have been made after the failure or whether the failure cause memory (unauthorized) has been deleted after a failure. The * time is displayed in hours, using the small digits (7 mm) as a makeshift.

m) Setting the filter interval: The operating time between two filter changes can be programmed with "Time", "Filter", entering a number and "Enter". Appears in the display the symbol "F", next to it on the 7 mm LEDs the four-digit filter interval in hours. B. adjustable in the range of 0 ^ filter interval = 2150 hours.

In order to demonstrate the possibility of programming, the following programming examples are given, for example a program in a table for the start / restart, which is also in the form of a flow chart

can be seen in FIGS. 9a, 9b and 9c.

The monitoring device according to the invention also includes a Special monitoring program in which all input signals are checked with regard to their limit values, see the flowchart in FIG. 10. When a limit value is reached, there is a jump to the fault, with a corresponding fault program can be seen with a flow chart in FIG. In addition, the last three are exceeded or not reached of limit values are stored in a "FIFO" memory area in order to enable a detailed error diagnosis within the framework of the fault program to enable. Next, at intervals of 15 min all values of input variables are stored in a FIFO area. This gives the opportunity for service to everyone Time, especially after a failure, to examine the history of the current operating status.

When limit values are reached within the scope of the start or monitoring program, a malfunction program is started which, see Fig. 12, reports the value that has reached one of its limit values by flashing display and by switching on an alarm device connected _{to Q 4.} In accordance with an error catalog, see Fig. 13, the cooling compressor, which is used to generate the coolant for the dryer, and possibly the _{compressed air-generating compressor controlled via Q 5} , may also be switched off (emergency stop).

After pressing the "Enter / Diagnose" key, see Fig. 6, appears an error code as shown in FIG. 13 appears on the display. This error table is stored in the program memory. If if the program memory is a so-called EPROM, this error table can be changed with relatively little effort or be expanded. If this error table has been established, however, the cheaper memory types ROM and PROM can also be used where programming is not possible or only possible under difficult circumstances.

BAD ORIGINAL _c0P y

The error table contains the type and sequence of the limit values above or Underrun and the information / whether the disturbance should only lead to an alarm or to an emergency stop.

In the case of particularly serious malfunctions that lead to damage of the system on restart / a start lock is provided, which can only be achieved by the already mentioned deletion process can be canceled.

With regard to the mechanical structure, reference is again made to FIG. 3 referenced, with a slightly larger board, z. B. Double Europe card will be useful. This also contains circuits to evaluate the measured variables, a computer consisting of a so-called "MCU" / a 1 KByte CMOS-RAM with a buffer battery for long-term use Data backup when the device is switched off, a program memory (EPROM) and interfaces to the keyboard, to the Evaluation circuits and to the outputs. Details do not need to be given since these are known to the person skilled in the art.

The adjustment elements for the sensors are accessible through holes in the rear cover.

Socket strips for inputs and outputs are directly on the board soldered, d. H. led out laterally.

The structure described is particularly economical in the Manufacture and enables high reliability, in particular because there is no free wiring. In addition, can connect a test device in a simple manner, with which the operation of the device and z. B. also the programming in a simpler way Way can be checked or changed.

The invention is not only suitable for compressed air systems, but also for z. B. the dehumidification and / or compression of gases in general. The drying can be done by; Be carried out by refrigeration dryers or by absorption dryers.

ES / j η 5 " ^C0P |

7.1 Start / setup type program .m

The program starts automatically after switching on the PICLJ and has the following sequence:

1 . "Start" LED on.

2. kJ Was "Stop" pressed earlier? If so, Jump to 4.

3. Is there a break? If not, jump to 5. 4th UJarten on actuation of "Start".

5. If the minimum of the temperature differences ^, .- and t.-, -. - t _r has dropped less than 1 C since switching off υ η, jump to 7.

E. Values up to t _n _. by Q ° C above t _rnr .., t _r and t_. liect. if the

UiL L υ υ LL ¹ J

Waiting time reached, jump to fault.

7. Cool k οιir. ρ ressor a.

8. Wait until t "reaches the range -1 ° C = t" = 5 ° C. if the 15 min reached b'artezsit, Kühlkompressox off - jump, to Stcrun

S. If there are no valve contacts, jump to 11.

ID. Check whether the bypass is closed, inlet and outlet ver. ti 1

open minded. If all conditions are met, jump to 19. 1 1. AbI ε? i ter open. .

12. Display "CPEN EYP" until bypass is open or "Enter" is pressed.

13. Display "OPEN IN" until entry valve 1 is opened or "Enter" is printed. If continued with "Enter", jump to 15.

U. waiting time 1min.

15. Close the arrester.

15. Check whether P _{1 is} within the required limits. If not, jump to the fault.

17. Display "OPEN OUT" until outlet valve 1 is open or "Enter" pressed.

16. Display "CLOSE BYP" until bypass is closed or "Enter" is printed.

19. Compressed air compressor on (connected Falb).

20. "Start" LED off.
21. "Operation" LED on.

22. Jump ru ~ practice ruiachungsp rograrr.m.

BATH ORIGINAL

Claims (13)

DR.-ING. Ernst Stratmann PATENT ANWALI
D-4000 DÜSSELDORF I · SCHADOWPLATZ'9 VNR: 109126 Düsseldorf, April 6, 1982 8213 VIA Gesellschaft für Verfahrenstechnik mbH
Düsseldorf 1 Patent claims: Method for monitoring a compressed air generation system comprising at least one compressor and one compressed air dryer, the sensors for recording operating data of the
Compressor and dryer, such as pressure and temperature
of compressed air, ambient air, cooling water and the like, as well as
Has display devices for such operating data,
characterized in that at least some of the monitored operating data (e.g. number of operating hours between two filter change processes, extreme values reached for pressure and
Temperature, etc.) can be stored electronically and displayed on the display device upon request. 2. The method according to claim 1, characterized in that the temporal by means of a programmable microprocessor
Course of certain operating data with predetermined time functions and / or with the course over time or with values
is linked at certain times and depending on the result of the link, different signals are output for the display devices. Postal check berlin west (bank code 100 100 10) I32736-IO9 deutsche bank (bank code 300 70 010) 6160253 3. The method according to claim 2, characterized in that the display generated by the signals and / or the function can be changed from input keys by entering a code. 4. The method according to any one of claims 1 to 3, characterized / that the display is alphanumeric by means of several groups of seven-part LEDs arranged in a row he follows. 5. Device for carrying out the method according to claim 1, with a microprocessor-controlled monitoring device for at least one compressor and one compressed air dryer Comprehensive compressed air generation system, the sensors for recording operating data of the compressor and dryer, such as pressure and temperature of compressed air, ambient air, Contains cooling water, oil and the like, as well as display devices for such operating data, characterized in that that the microprocessor (50) of the monitoring device (40) has a comparison arrangement for comparing the individual Operating data with stored setpoints and a downstream link arrangement for linking the size of the deviations, a clock device for determining the chronological sequence of the occurrence of the deviation of the Has operating data and a time function memory to which the chronological order of occurrence of the operating data deviations are supplied and a corresponding display to the display devices when specified setpoints are exceeded (42, 43) yields. 6. Monitoring device according to claim 5, characterized in that that the monitoring device is followed by a control device that controls the operation of the compressor (14), the dryer (20) and / or the condensate drain (22) affected. 7. Monitoring device according to claim 5 or 6, characterized in that the monitoring device has a diagnostic device is connected downstream, which has a function memory with stored typical data deviation behavior in the event of certain malfunctions and an actuating device, the corresponding malfunction display devices is able to activate. - ■ 8. Monitoring device according to claim 7, characterized in that " that the display is a code display (Fig. 8). 9. Monitoring device according to one of claims 5 to 8, characterized in that a data storage device and an associated activation device are provided is to save data in the event of a fault. 10. Monitoring device according to one of claims 5 to 9, characterized in that the display devices (42) consist of a plurality of seven segments each comprising light-emitting Diodes (LED) (76) consists, with at least two LED groups of different LED color or LED size available. - 11. Monitoring device according to claim 10, characterized in that that the display device (42) consists of three LED groups arranged side by side, the middle « Group has smaller LEDs than the first and the last group, preferably about half the size of LEDs. 12. Monitoring device according to claim 11, characterized in that that the first group consists of only one LED and the second group at least five and the third group has at least three LEDs. BATH ORIGINAL 13. Monitoring device according to one of claims 5 to 12, characterized in that an operating keypad (70) is provided, preferably made up of 4x4 pushbuttons (72). Description;