DE2542025B2 - Electronic heat meter - Google Patents
Electronic heat meterInfo
- Publication number
- DE2542025B2 DE2542025B2 DE19752542025 DE2542025A DE2542025B2 DE 2542025 B2 DE2542025 B2 DE 2542025B2 DE 19752542025 DE19752542025 DE 19752542025 DE 2542025 A DE2542025 A DE 2542025A DE 2542025 B2 DE2542025 B2 DE 2542025B2
- Authority
- DE
- Germany
- Prior art keywords
- pressure
- solenoid valves
- heat meter
- measuring lines
- measuring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000523 sample Substances 0.000 claims description 14
- 230000003068 static effect Effects 0.000 claims description 5
- 230000032683 aging Effects 0.000 description 4
- 230000007774 longterm Effects 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000012935 Averaging Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
- G01F1/34—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by measuring pressure or differential pressure
- G01F1/36—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by measuring pressure or differential pressure the pressure or differential pressure being created by the use of flow constriction
- G01F1/40—Details of construction of the flow constriction devices
- G01F1/46—Pitot tubes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K17/00—Measuring quantity of heat
- G01K17/06—Measuring quantity of heat conveyed by flowing media, e.g. in heating systems e.g. the quantity of heat in a transporting medium, delivered to or consumed in an expenditure device
- G01K17/08—Measuring quantity of heat conveyed by flowing media, e.g. in heating systems e.g. the quantity of heat in a transporting medium, delivered to or consumed in an expenditure device based upon measurement of temperature difference or of a temperature
- G01K17/10—Measuring quantity of heat conveyed by flowing media, e.g. in heating systems e.g. the quantity of heat in a transporting medium, delivered to or consumed in an expenditure device based upon measurement of temperature difference or of a temperature between an inlet and an outlet point, combined with measurement of rate of flow of the medium if such, by integration during a certain time-interval
- G01K17/12—Indicating product of flow and temperature difference directly or temperature
- G01K17/16—Indicating product of flow and temperature difference directly or temperature using electrical or magnetic means for both measurements
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K17/00—Measuring quantity of heat
- G01K17/06—Measuring quantity of heat conveyed by flowing media, e.g. in heating systems e.g. the quantity of heat in a transporting medium, delivered to or consumed in an expenditure device
- G01K17/08—Measuring quantity of heat conveyed by flowing media, e.g. in heating systems e.g. the quantity of heat in a transporting medium, delivered to or consumed in an expenditure device based upon measurement of temperature difference or of a temperature
- G01K17/10—Measuring quantity of heat conveyed by flowing media, e.g. in heating systems e.g. the quantity of heat in a transporting medium, delivered to or consumed in an expenditure device based upon measurement of temperature difference or of a temperature between an inlet and an outlet point, combined with measurement of rate of flow of the medium if such, by integration during a certain time-interval
- G01K17/12—Indicating product of flow and temperature difference directly or temperature
- G01K17/18—Indicating product of flow and temperature difference directly or temperature using electrical or magnetic means for one measurement and mechanical means for the other
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Fluid Mechanics (AREA)
- Measuring Fluid Pressure (AREA)
- Testing Or Calibration Of Command Recording Devices (AREA)
- Measuring Volume Flow (AREA)
Description
Die Erfindung bezieht sich auf einen elektronischen Wärmezähler mit einem dem Durchfluß des Mediums dienenden rohrförmigen, mindestens eine Drucksonde aufweisenden Körper, dem elektromechanische bzw. elektronische Glieder zum Umwandeln des Drucksondensignals in eine proportionale elektrische Spannung und daraus in ein dem Durchfluß proportionales Signal zugeordnet sind, sowie einem analog arbeitenden Rechenwerk und Temperaturfühler, wobei die Drucksonde den Staudruck des fließenden Mediums zum Zwecke des Eliminierens des statischen Druckes als Differenzdruck aufnimmt, und mit einem Druckspannungswandler mit zwei Meßleitungen und einem Radizierglied.The invention relates to an electronic heat meter with a flow of the medium Serving tubular body having at least one pressure probe, the electromechanical or electronic members for converting the pressure probe signal into a proportional electrical voltage and from this are assigned a signal proportional to the flow rate, as well as an analog operating signal Arithmetic unit and temperature sensor, with the pressure probe measuring the dynamic pressure of the flowing medium Purposes of eliminating static pressure as differential pressure records, and using a compressive voltage transducer with two measuring lines and a square root.
Es sind bereits elektronische Wärmezähler bekannt, bei denen der Durchfluß des Mediums allgemein über die Strömungsgeschwindigkeit ermittelt wird, im speziellen durch die Anwendung des Wirkdruck- bzw. Staudruckverfahrens. Diese Geräte benötigen eine Umsetzung des Druck- bzw. Differenzdrucksignals in ein Spannungs- oder Stromsignal. Die mit diesen Geräten gewonnenen Erkenntnisse und Erfahrungen ^o haben jedoch gezeigt, daß diese Wandler (Druck in Spannung bzw. Druck in Strom) hinsichtlich ihres Langzeitverhaltens nicht zufriedenstellend arbeiten. Durch Alterung und Druckabhängigkeiten wie auch durch Temperatureinflüsse, die in der Regel auch die nachgeschaltete Elektronik betreffen, ergeben sich Änderungen des Meßwertes, die die angestrebte Genauigkeit des Gerätes vermindern und das Langzeitverhalten verschlechtern. Electronic heat meters are already known in which the flow of the medium generally exceeds the flow velocity is determined, in particular by using the differential pressure resp. Dynamic pressure process. These devices require the pressure or differential pressure signal to be converted into a voltage or current signal. The knowledge and experience gained with these devices ^ o have shown, however, that these converters (pressure in voltage or pressure in current) with regard to their Long-term behavior does not work satisfactorily. By aging and pressure dependencies as well due to temperature influences, which usually also affect the downstream electronics Changes in the measured value, which reduce the desired accuracy of the device and worsen the long-term behavior.
Angesichts dieser, den bekannten elektronischen fco Wärmezählern anhaftenden Unzulänglichkeiten hat sich die vorliegende Erfindung die Aufgabe gcslelll, einen einfachen und preiswerten elektronischen Wärmezähler zu schaffen, bei dem die Einflüsse von Temperatur, Druck und Alterung am Druckspannungs- br> wandler ausgeschaltet werden und damit das Lang/eilverhalten des Meßsystems verbessert wird.In view of this, the well-known electronic fco heat meters adhering shortcomings, the present invention has the task gcslelll to provide a simple and inexpensive electronic heat meters, in which the influences of temperature, pressure and aging are turned on Compression strength b r> converter and thus the Long / fast behavior of the measuring system is improved.
Aussehend von einem elektronischen Wärmezähler mit einem Durchfluß des Mediums dienenden rohrförmigen, mindestens eine Drucksonde aufweisenden Körper, dem elekiromechanische bzw. elektronische Glieder zum Umwandeln des Drucksondensignals in eine proportionale elektrische Spannung und daraus in ein dem Durchfluß proportionales Signal zugeordnet sind, sowie einem analog arbeitenden Rechenwerk und Temperaturfühler, wobei die Drucksonde den Staudruck des fließenden Mediums zum Zwecke des Eliminierens des statischen Druckes als Differenzdruck aufnimmt, und mit einem Druckspannungswandler mit zwei Meßleitungen und einem Radizierglied, wird die vorgenannte Aufgabe dadurch gelöst, daß Magnetventile in den Meßleitungen angeordnet sind, daß die Magnetventile zum Zweck des Nullabgleiches periodisch die Meßleitungen sperren und den Differenzdruck am Druckspannungsvanüler auf Null bringen, und daß die Magnetventile bistabil sind.Looking from an electronic heat meter with a flow of the medium serving tubular, at least one body having a pressure probe, the electromechanical or electronic Members for converting the pressure probe signal into a proportional electrical voltage and therefrom into a signal proportional to the flow are assigned, as well as an analog arithmetic unit and Temperature sensor, the pressure probe measuring the dynamic pressure of the flowing medium for the purpose of Eliminating the static pressure as differential pressure picks up, and using a pressure-voltage converter with two measuring lines and a square root, the aforementioned object is achieved in that solenoid valves are arranged in the measuring lines that the solenoid valves periodically for the purpose of zeroing block the measuring lines and bring the differential pressure at the pressure voltage vanuler to zero, and that the solenoid valves are bistable.
Durch diese Ausführung wird erreicht, daß der Nullpunkf des Druckspannungswandlers periodisch beim Abgleich überprüft und gegebenenfalls nachgeregelt wird. Würde dies nicht geschehen, dann würden Einflüsse v/h Temperatur- und Druckänderungen sowie Alterung die Meßgenauigkeit entscheidend herabsetzen. This embodiment ensures that the zero point of the pressure voltage converter is checked periodically during the adjustment and readjusted if necessary. If this were not to happen, influences v / h changes in temperature and pressure as well as aging would decisively reduce the measurement accuracy.
Der Nullabgleich kann in unterschiedlichen Zeitabständen erfolgen, wodurch der Vorteil erzielt wird, daß das Meßsystem an die jeweils herrschenden Betriebsbedingungen angepaßt werden kann. Durch die Magnetventile wird eine hohe Betriebssicherheit erreicht, außerdem handelt es sich hier um standardisierte Bauteile, die einfach auszutauschen sind. Im übrigen erweist es sich auch als Vorteil, daß durch den selbsttätigen und regelmäßigen Nullabgleich das Langzeitverhalten bzw. die Standzeit des Wärmezählers entscheidende Verbesserungen erfährt.The zero adjustment can take place at different time intervals, which has the advantage that the measuring system can be adapted to the prevailing operating conditions. Through the solenoid valves a high level of operational reliability is achieved, and these are also standardized Components that are easy to replace. In addition, it also proves to be an advantage that the automatic and regular zero adjustment, the long-term behavior or the service life of the heat meter undergoes decisive improvements.
Durch die bistabilen Magnetventile ergibt sich ein weiterer Vorteil der Energieeinsparung, da zum Schalten der Ventile in beide Richtungen jeweils nur ein kurzer Impuls, d. h. kein Dauerstrom erforderlich ist. Dies ist entscheidend, wenn das Gerät mit einer Batterie, d. h. ohne Netzspannungsversorgung betrieben wird, da in diesem Fall der gesamte Energieverbrauch möglichst gering sein muß.The bistable solenoid valves result in a further advantage in terms of energy savings, since for Switching the valves in both directions only with a short pulse, i. H. no continuous current is required. This is critical if the device is running on a battery, i.e. H. operated without mains voltage supply because in this case the total energy consumption must be as low as possible.
In der Zeichnung ist die Erfindung an einem Ausführungsbeispiel, das eine schematische Darstellung der Durchflußmeßeinrichtung für den Wärmezähler veranschaulicht, dargestellt.In the drawing, the invention is based on an exemplary embodiment, which is a schematic representation the flow meter for the heat meter illustrates, shown.
Der in seiner Gesamtheit nicht dargestellte elektronische Wärmezähler ist mit einem dem Durchfluß des Mediums dienenden rohrförmigen Körper 1 ausgestattet, dem eine Drucksonde 2 zugeordnet ist. Die einen Mittelwert bildende Drucksonde 2, die einerseits den besonderen Vorteil eines großen Meßbereiches aufweist, und die andererseits eine genaue Stabilität der Meßgenauigkeit gewährleistet, da keine Verschmutzung und Abnutzung derselben eintritt, nimmt den Staudruck des durch den Körper 1 fließenden Mediums zum Zwecke des Eliminierens des statischen Druckes als Differenzdruck auf.The electronic heat meter, not shown in its entirety, is connected to the flow of the Tubular body 1 serving the medium, to which a pressure probe 2 is assigned. The one Averaging pressure probe 2, which on the one hand has the particular advantage of a large measuring range, and which, on the other hand, ensures precise stability of the measurement accuracy, since there is no contamination and wear and tear of the same occurs, the dynamic pressure of the medium flowing through the body 1 decreases for the purpose of eliminating the static pressure as differential pressure.
Dem Körper 1 sind ferner elektromechanische bzw. elektronische Glieder zum Umwandeln des Drucksondensignals in eine proportionale elektrische Spannung zugeordnet: Die Drucksonde 2 ist über Meßleitungen 3 mit einem Druckspaniuingswandler 4 verbunden. In den Meßleitungen 3 sind Magnetventile 5 angeordnet. Die Meßleitungen 3 dienen im Betriebsfall zur Aufrechlerhaltung einer direkten hydraulischen VerbindungThe body 1 are also electromechanical or electronic members for converting the pressure probe signal Assigned to a proportional electrical voltage: The pressure probe 2 is connected via measuring lines 3 connected to a Druckspaniuingswandler 4. In the Measuring lines 3, solenoid valves 5 are arranged. The measuring lines 3 are used for maintenance maintenance during operation a direct hydraulic connection
zwischen dem Druckspannungswandler 4 und der Drucksonde 2.between the pressure voltage converter 4 and the pressure probe 2.
Zum Beseitigen von Temperaturdriften und Alterungsabweichungen wird am Druckspannun<*swandler 4 periodisch ein selbsttätiger Nullabgleich vorgenommen. Zum Zweck des Nullabgleiches sperren hierbei die aus Energiegründen ein bistabiles Verhalten aufweisenden Magnetventile 5 periodisch die Meßleitungen 3 zum Körper 1 ab, gleichzeitig wird der Differenzdruck am Druckspannungswandler 4 auf Null abgesenkt, während hingegen der statische Druck erhalten bleibt.To eliminate temperature drifts and aging deviations, the pressure voltage converter 4 an automatic zero adjustment is carried out periodically. For the purpose of zero adjustment, they lock out Energy reasons a bistable behavior exhibiting solenoid valves 5 periodically the measuring lines 3 to Body 1 from, at the same time the differential pressure at the pressure-voltage converter 4 is lowered to zero, while however, the static pressure is retained.
Hierzu 1 Blatt Zeichnungen1 sheet of drawings
Claims (2)
Priority Applications (11)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19752542025 DE2542025C3 (en) | 1975-09-20 | 1975-09-20 | Electronic heat meter |
| GB3617176A GB1558884A (en) | 1975-09-20 | 1976-09-01 | Electronic heat quantity meter |
| BE170385A BE845894A (en) | 1975-09-20 | 1976-09-06 | ELECTRICAL HEAT QUANTITY METER |
| CH1148676A CH627273A5 (en) | 1975-09-20 | 1976-09-09 | Electronic heat flow meter |
| SE7610151A SE7610151L (en) | 1975-09-20 | 1976-09-14 | ELECTRONIC MEASUREMENT METER |
| AT686176A ATA686176A (en) | 1975-09-20 | 1976-09-15 | ELECTRONIC HEAT AMOUNT |
| NL7610331A NL7610331A (en) | 1975-09-20 | 1976-09-16 | ELECTRONIC HEAT AMOUNT COUNTER. |
| DK420176A DK420176A (en) | 1975-09-20 | 1976-09-17 | ELECTRONIC HEAT AMOUNT |
| IT2736076A IT1073308B (en) | 1975-09-20 | 1976-09-17 | ELECTRONIC HEAT WITH A CALCULATION BODY IN ANA LOGIC TECHNIQUE |
| FR7628205A FR2325029A1 (en) | 1975-09-20 | 1976-09-20 | ELECTRONIC HEAT QUANTITY METER |
| US05/862,679 US4157034A (en) | 1975-09-20 | 1977-12-21 | Electronic heat amount meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19752542025 DE2542025C3 (en) | 1975-09-20 | 1975-09-20 | Electronic heat meter |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| DE2542025A1 DE2542025A1 (en) | 1976-10-07 |
| DE2542025B2 true DE2542025B2 (en) | 1980-08-07 |
| DE2542025C3 DE2542025C3 (en) | 1981-03-12 |
Family
ID=5957002
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE19752542025 Expired DE2542025C3 (en) | 1975-09-20 | 1975-09-20 | Electronic heat meter |
Country Status (10)
| Country | Link |
|---|---|
| AT (1) | ATA686176A (en) |
| BE (1) | BE845894A (en) |
| CH (1) | CH627273A5 (en) |
| DE (1) | DE2542025C3 (en) |
| DK (1) | DK420176A (en) |
| FR (1) | FR2325029A1 (en) |
| GB (1) | GB1558884A (en) |
| IT (1) | IT1073308B (en) |
| NL (1) | NL7610331A (en) |
| SE (1) | SE7610151L (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3208511A1 (en) * | 1982-03-09 | 1983-09-22 | Siemens AG, 1000 Berlin und 8000 München | HEAT METER |
| DE4408421C2 (en) * | 1994-03-12 | 1996-01-11 | Iwk Regler Kompensatoren | Method and device for differential pressure measurement with periodic zero adjustment |
| GB2291506B (en) * | 1994-07-22 | 1998-08-19 | British Gas Plc | Apparatus for measuring the flow rate of a fluid |
| DE102013114495A1 (en) * | 2013-12-19 | 2015-06-25 | S.K.I. GmbH | Method and measuring arrangement according to the differential pressure principle with zero point adjustment |
| CN105004450A (en) * | 2015-08-03 | 2015-10-28 | 浙江华德利纺织印染有限公司 | Heat measuring method and apparatus of conduction oil |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR545418A (en) * | 1921-12-30 | 1922-10-11 | Heat meter | |
| DE547142C (en) * | 1926-06-24 | 1932-03-23 | Siemens & Halske Akt Ges | Heat meter with thermocouples in flow and return and flow meter in the form of a differential pressure meter |
| US2804773A (en) * | 1955-09-19 | 1957-09-03 | Henze Instr And Valve Inc | Temperature sensing devices |
| FR1247036A (en) * | 1959-01-09 | 1960-11-25 | Askania Werke Ag | Device for measuring quantities of heat |
| FR2157099A5 (en) * | 1971-10-18 | 1973-06-01 | Schlumberger Compteurs | |
| DE2320359A1 (en) * | 1973-04-21 | 1974-11-07 | Nortron Hermann Koehler Elektr | HEAT COUNTER |
| FR2305807A1 (en) * | 1975-03-27 | 1976-10-22 | Fisch Raymond | Electronic system for measuring calorific losses - using signal representing fluid temp. difference |
-
1975
- 1975-09-20 DE DE19752542025 patent/DE2542025C3/en not_active Expired
-
1976
- 1976-09-01 GB GB3617176A patent/GB1558884A/en not_active Expired
- 1976-09-06 BE BE170385A patent/BE845894A/en unknown
- 1976-09-09 CH CH1148676A patent/CH627273A5/en not_active IP Right Cessation
- 1976-09-14 SE SE7610151A patent/SE7610151L/en unknown
- 1976-09-15 AT AT686176A patent/ATA686176A/en not_active Application Discontinuation
- 1976-09-16 NL NL7610331A patent/NL7610331A/en not_active Application Discontinuation
- 1976-09-17 IT IT2736076A patent/IT1073308B/en active
- 1976-09-17 DK DK420176A patent/DK420176A/en not_active Application Discontinuation
- 1976-09-20 FR FR7628205A patent/FR2325029A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| FR2325029B1 (en) | 1982-10-22 |
| DE2542025A1 (en) | 1976-10-07 |
| DK420176A (en) | 1977-03-21 |
| FR2325029A1 (en) | 1977-04-15 |
| DE2542025C3 (en) | 1981-03-12 |
| NL7610331A (en) | 1977-03-22 |
| SE7610151L (en) | 1977-03-21 |
| IT1073308B (en) | 1985-04-17 |
| CH627273A5 (en) | 1981-12-31 |
| GB1558884A (en) | 1980-01-09 |
| BE845894A (en) | 1976-12-31 |
| ATA686176A (en) | 1986-08-15 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C3 | Grant after two publication steps (3rd publication) | ||
| 8339 | Ceased/non-payment of the annual fee |