WO1998048249A1

WO1998048249A1 - Device and method for checking supply meters, specially water meters in houses and apartments

Info

Publication number: WO1998048249A1
Application number: PCT/EP1998/002325
Authority: WO
Inventors: Uwe Matheisen
Original assignee: Imcon Gesellschaft Für Bildverarbeitungs-, Steuer-, Regel- Und Messtechnik Mbh
Priority date: 1997-04-23
Filing date: 1998-04-20
Publication date: 1998-10-29
Also published as: DE19717128A1; EP1012544A1

Abstract

When checking supply meters, specially water meters in houses and in apartments, it is quite useful to carry out monitoring or checking or adjustment on the spot. As a general rule, this involves a considerable amount of equipment to measure the water flow passing through the supply meter. A compact and cost-effective checking device can be obtained by using a fixed-volume type pump, enabling adjustment and simultaneous measurement of said water flow.

Description

Device and method for testing consumption meters, in particular house water meters and _d

Apartment water meters

DESCRIPTION

The present invention relates to an apparatus and a method for testing consumption meters, in particular house water meters and apartment water meters, according to the preamble of claim 1 and claim 6, respectively.

Consumption meters, such as electricity, gas and water meters, are calibrated meters that measure a customer's consumption by accessing the distribution network. has different connection points. The consumption meters are usually at the customer's connection point to the

Distribution network installed and are read regularly. In accordance with the value read, billing takes place for a consumption period concluded with the reading. In order to ensure correct billing, the consumption meters must be checked at regular intervals and, if necessary, repaired and re-calibrated. So far, this has been done in such a way that the consumption meters installed at the point of use have been removed and then checked at a central measuring or testing point. The one upgraded at the customer

The consumption meter had to be replaced by another consumption meter in order to continue to monitor consumption. If the validity period of a consumption meter has expired, it has always been replaced by a new meter or Measuring insert replaced. The exchange for new consumption meters occurs regardless of the fact that used consumption meters could be used again after cleaning and / or repair as well as a new calibration or certification. In connection with measuring accuracy deviations of consumption meters due to deposits and calcification, it should be noted that cleaning with appropriate brushes and cleaners is possible, which allows the meters to be reused.

Due to a legal requirement that hot and cold water meters are to be installed in all new buildings for billing by apartment, the control or reading of a large number of consumption meters is required. Here, however, there is the problem that in new buildings

Meter housings are usually installed in a flush-mounted construction, and thus a simple removal of the consumption meter is not possible without problems. In order to avoid this problem, a counter change in these counters can consist in replacing a calibrated measuring cartridge that is independent of the housing. However, due to deposits of suspended matter or limescale deposits in the water meters, which cause a reduction in cross-section in the area of the inlet and outlet section, which in turn leads to an increased flow, the meter is used over the course of its operating life

Measurement inaccuracies or inadmissible exceedances of the error tolerances. A suitable test, monitoring or calibration is also necessary here.

Since 1.1.1993 the possibility exists that

Extend the validity period of water meters by carrying out random checks by three years each. In this regard, it is desirable to test with a suitable, flexible measuring device on site. The possibility of being able to measure the accuracy of consumption meters at the consumption source can therefore deal with customer complaints on-site to reduce conflict.

A device and a method for testing consumption meters with optical detection of the measured variable is known for example from DE 39 01 816 AI. It describes a method for testing consumption meters, in particular electricity, gas and water meters, in which a focused light beam is directed onto a rotating element that is visible from the outside, the so-called starter star of the consumption meter, the scope of which is designed in a regular manner in such a way that that the laser beam is subjected to different reflection conditions. The reflected laser beam experiences a change in intensity as a function of the reflection conditions, which opens up the possibility of determining the rotational speed of the starting star of the consumption meter on the basis of its known geometry. Since the starter is actuated directly by the meter of the consumption meter and set in rotation, the counting of the _. Lichtintensitätsi pulse can be deduced from the measurement result, taking into account the design data of the consumption meter. For this purpose, the known device has both a receiver for the reflected laser beam and an evaluation unit with a pulse counter. There are also water meters with (fixed) pulse generators.

A fundamental problem of the known devices and methods for testing consumption meters is that very large and / or expensive devices must be provided for measuring the flow or the volume of the medium flowing through the consumption meter. Weighing scales are used to weigh the amount of medium collected in a container over a given period of time and thus enable the volume and flow rate to be determined. The use of flow sensors in cooperation with control valves is also known. While the flow sensors can be implemented comparatively easily and with a small size, the

Control valves are complex and complex elements, so that devices with flow sensors and control valves as well as devices with scales and receptacles are always very large and complex. These devices and the methods that can be carried out with them are not suitable for mobile use and are only implemented once at stationary test stations for cost reasons.

The invention is therefore based on the object of a device and a method for testing

To provide consumption meters, in particular house water meters and apartment water meters, with which an inspection and certification (verification) of house and apartment water meters can also be carried out on site with regard to random checks of consumption meters.

This object is achieved by the device described in claim 1 and by the method described in claim 6. Advantageous refinements result from the subclaims.

A central idea here is that the setting of the constant flow of the consumption meter supplied medium is carried out automatically by a fixed volume pump, so that the flow flowing through the consumption meter within a certain time interval and the volume is automatically predetermined and measurable.

According to the invention, a fixed-volume pump is understood to mean any type of pump which conveys constant volumes due to its construction, so that, for example, the volume delivered by the pump per unit of time and thus the flow can be set by adjusting the speed. An example of a fixed volume pump is a gear pump that conveys the medium with constant volume units. Fixed volume pumps are characterized by the fact that, by design, they allow the flow to be set by controlling the pump. This eliminates the need to measure flow. In other words, the fixed volume pump is not only used for setting but also for measuring the flow rate. For active operation, that is to say in the event that the fixed volume pump actively conveys the medium through the consumption meter to be checked, the fixed volume pump works in the conventional sense as a pump. In passive operation, the fixed volume pump only adjusts the flow through the consumption meter that is otherwise promoted and is comparable to a control valve.

What is achieved through the use of the fixed volume pump is that a compact and inexpensive test device can be implemented, that on the one hand enables mobile use and that in stationary operation the use of several test devices in parallel operation is permitted. These advantages are explained in detail again below. An advantage achieved by the invention is, in particular, that a portable test device and a corresponding method are provided for the checking and certification of consumption meters, in particular house water meters and apartment water meters. Due to a more compact embodiment compared to previous measuring devices, a variable use is possible. This in turn represents an improved service for the customer.

Another advantage of the invention is that a sample test of water meters is also possible on site by mobile use of the test device, and the calibration validity period of the corresponding meters can thus be easily extended. In connection with the previously cited legislative proposal from January 1st, 1993, which enables an extension of the validity period of corresponding meters, the consumption meter can be checked, certified or verified at any time. This enables a more economical use of consumption meters.

In stationary use, the test device according to the invention is also suitable for testing consumption meters that are to be newly calibrated; the device according to the invention can be used advantageously.

The performance of a consumption meter test stand can be increased by arranging, for example, three measuring devices connected in parallel, since time-optimized use of the test personnel is made possible. In this way, a test cycle can be achieved which enables an uninterrupted measurement of the consumption meters to be verified. A detailed description of the device according to the invention and the method according to the invention is given below with reference to the drawings.

Show it:

FIG. 1 shows a schematic arrangement of the measuring device for checking and calibrating permanently installed consumption meters;

Figure 2 is a schematic representation of a

Consumption meter tester of Fig.l, which comprises a fixed volume pump;

Figure 3 is a detailed schematic illustration of the consumption meter tester of Figures 1 and 2;

Figure 4 is a schematic arrangement of a test bench according to the invention.

Figure 1 shows a schematic arrangement of an embodiment of a device according to the invention, which is used for mobile use for the measurement or testing of built-in consumption meters. The consumption meter 1 is shown in this case as a built-in water meter.

Corresponding valve connections 2a, 2b to the water circuit are shown. The water meter shown schematically is a consumption meter with a mechanical counter which shows the water flow via a corresponding display 3 of a sequence of digits. As in

Figure 1 shown, the display of the water meter is detected by a reading device 12, which is either based on an optoelectronic detection or via a Pulse sampling takes place. The information detected by the reading device 12 is passed to a control unit 11 of the test device 10. For this purpose, the control unit 11 comprises a data storage device (not shown) and a data processing device (not shown), and also controls the point in time at which the consumption meter display is recorded. The principle of the measuring method is based on the fact that a constant flow of the medium flowing through the consumption meter is set. According to the invention, this is ensured by a fixed volume pump 13 in the test device 10.

The fixed volume pump 13 can be, for example, a gear pump or a similar pump. Motor-driven, speed-controlled pumps of this type ensure the transport of a certain, fixed volume. The flow setting and the flow measurement, as well as the measurement of the volume as an integral of the flow rate are realized via the exact speed control and measurement of the drive shaft of the pump. Thus, the fixed volume pump of the device according to the invention combines the functions of setting flow and measuring flow and volume. The individual setting parameters are controlled by the control unit 11.

The display of the consumption counter is detected by the reading device 12 at a start time (tl) and an end point (t2) of a time interval. This information is forwarded to the control unit 11. During this time interval there is a constant flow of flow in the consumption meter. For this purpose, the medium flows from a tapping point 14 to the test device 10, there through the fixed volume pump 13 and from the test device 10 to an outlet 16. The tapping point 14 is, for example, bathroom or kitchen fittings. The fixed volume pump 13 may be operating in passive mode.

The consumption meter can be checked by detecting the display of the water meter at a time (t1), by setting a constant flow of the medium flowing through the consumption meter and by detecting the display of the meter at a later time (t2). This is where the

Evaluation of the test data by the control device 11, which stores the information from the reading device 12 and the operating data of the fixed volume pump 13 and uses these to determine the measurement result.

2 shows the test device according to the invention in a different form and the use of the test device according to the invention for testing water meters which have been removed or newly calibrated is discussed. The core component of the test device is the fixed volume pump 13, which is arranged in a water circuit, to which the consumption meter 1 and a buffer tank 4 also belong. The buffer container 4 serves to provide a sufficient amount of the medium flowing through the consumption meter 1 and to compensate for fluctuations. The display 3 of the consumption meter 1 is scanned by a reading device 12 which is connected to a control unit 11. This control unit is also connected to the fixed volume pump 13 in order to control its operation. This is the active operation of the fixed volume pump 13, which conveys the medium stored in the buffer tank 4 through the consumption meter. The control unit 11, the reading device 12 and the fixed volume pump 13 are components of the previously described mobile testing device (cf. FIG. 1). The buffer tank 4 is additionally provided for testing removed water meters.

FIG. 3 shows a further embodiment of the invention which, in addition to the testing of built-in consumption meters, can also be used to measure or check consumption meter housings with so-called interchangeable control measuring cartridges. This

Control measuring cartridges 17, which are interchangeably inserted in permanently installed consumption meters, can be inserted into the testing device 10 as shown in FIG. 3. Here too, as previously explained in connection with FIG. 1, a constant flow state is established by the fixed volume pump 13. By detecting the display of the consumption counter, the measurement process in turn is carried out in the control unit 11 at two different times (tl, t2) and by the characteristic data of the fixed volume pump.

According to a corresponding legal template, the test procedure for domestic water meters must be carried out in three specific states (different flow rates Q _max , Q-tren ^unci Q-min). In conventional measuring devices, regulation was previously carried out first at a maximum flow (Qmax). Following this test, the meters were then usually transported manually or automatically to a further test station and, after the ventilation required by the conversion, to another medium-sized one

(Qtren) ^unc a minimum flow (Q _m i _n) checked, which requires a relatively large effort. In contrast, in the device according to the invention, one and the same test bench the measurement is carried out at different flow rates that can be set one after the other. This is in turn made possible by the use of the fixed volume pump 13. As previously mentioned, the various flows are set via the speed control of the pump used. The arrangement according to the invention thus results in a small, light-weight apparatus which can be used universally as a portable test device for testing or calibrating consumption meters on site.

Finally, it should be mentioned that an increase in the performance of a test bench can be achieved by a parallel arrangement of several test devices according to the invention as shown in FIG. In the case of a stationary use of the test bench according to the embodiment in FIG. 4, the test person sets a flow Q _ax for measuring a first counter. The test at Qtren ^unci Qmin then runs automatically. With the aforementioned water meters of nominal size 2.5 m ^ / h, this typically takes 2 minutes. At the beginning of the automatic test of the first counter, the test person installs the second counter and adjusts it by the second measuring device at a flow rate Q _ma χ. Experience has shown that this also takes less than 2 minutes. Here, too, the automatic testing of the two further different flows (Q _m in ^and d Qtren) starts. • The same is done for the testing of the third meter by the third measuring device. Following the adjustment of the third counter, the test of the first counter has already been completed and can therefore be replaced automatically or manually. Access can now begin again so that an uninterrupted measuring cycle can be carried out.

Claims

claims

1. Device for checking consumption meters, in particular house water meters and

Apartment water meters, with

a fixed volume pump (13) nd

- a control unit for controlling the fixed volume pump (13),

because of the fact that

the fixed volume pump (13) both in an active

State in which the fixed volume pump (13) conveys the medium flowing through the consumption meter, and can also be operated in a passive state in which the fixed volume pump (13) adjusts the flow of the medium flowing through the consumption meter.

2. Device according to claim 1, characterized in that the flow of the medium flowing through the consumption meter is adjustable by adjusting the speed of the fixed volume pump.

3. Apparatus according to claim 1 or 2, characterized in that the fixed volume pump is suitable to set one of at least three different flow rates (Qm_ax 'Q-tren' Q-min).

4. Device according to one of claims 1 to 3, characterized in that the fixed volume pump is a gear pump or a similarly operating pump.

5. Device according to one of claims 1 to 4, characterized in that a reading device (12) is provided for detecting the display of the consumption meter and that the reading device is connected to the control unit.

6. Procedure for testing consumption meters, in particular house water meters and apartment water meters, with

a fixed volume pump (13) and

a control unit for controlling the fixed volume pump (13);

comprising the steps:

Selecting an active state of the fixed volume pump (13) in which the fixed volume pump (13) conveys the medium flowing through the consumption meter;

Select a passive state of the fixed volume pump

(13), in which the fixed volume pump (13) adjusts the flow rate of the medium flowing through the consumption meter.

7. The method according to claim 6, characterized in that one of at least three different flows (Qrr _. Ax 'Qtren'Q in) is set constant. Test stand for testing consumption meters, in particular house water meters and apartment water meters, characterized by the parallel arrangement of at least three devices according to one of claims 1 to 5.