The Legal System of Units of Measure, as well as the general principles and norms to which the organization and the legal regime of the metrological activity in Spain will have to adjust, are currently established by the Law 3/1985, of March 18, of Metrology, one of whose key pieces has been the establishment of a metrological control by the State, to which they must submit, in defense of the security, the protection of the health and the interests (a) consumers and users, all the instruments, equipment, means and systems of measurement, which serve to weigh, measure or count, and which has been developed by Royal Decree 1616/1985 of 11 September.

Produced the accession of Spain to the European Communities, by Royal Decree-Law 1296/1986, of 28 June, the Law of Metrology is amended to adapt it to the secondary Community law, establishing itself, in addition to the control of the State, a special metrological control, with effect within the scope of the European Economic Community, known as the EEC Metrological Control, which shall apply, if the control equipment available to the State so permits, to the measuring instruments and to methods of metrological control regulated by a specific Community Directive European Economic, and which has been regulated by Royal Decree 597/1988 of 10 June.

Between the Community rules governing measuring instruments and methods of metrological control, Directive 75 /33/EEC of 17 December 1974 on the approximation of the laws of the Member States relating to the approximation of the laws of the Member States members on cold water meters.

This Order has no other purpose than to incorporate the aforementioned Directive into Spanish national law, and it is issued in use of the authorization granted to the Ministry of Public Works and Urbanism for the final disposition of the Royal Decree 597/1988 of 10 June 1988 regulating the EEC Metrological Control.

By virtue,

DISPONGO:

First.

The cold water meters described in the Annex to this Order shall be subject to the metrological control of model approval and primitive verification, which shall be carried out in accordance with the provisions of the Royal Decree 597/1988 of 10 June 1988 regulating the EEC Metrological Control or, where appropriate, in accordance with the provisions of Royal Decree 1616/1985 of 11 September 1985 establishing the metrological control carried out by the Administration of the State.

Second.

The metrological control referred to in the previous paragraph shall be carried out by the Spanish Metrology Center of the Ministry of Public Works and Urbanism, in accordance with the technical specifications mentioned in the aforementioned Annex.

FINAL DISPOSITION

This Order shall enter into force on the day following that of its publication in the "Official State Gazette".

Madrid, December 28, 1988.

COCULLUELA SAENZ

Ilmos. Mr Deputy Secretary of Public Works and Urbanism and Director General of the National Geographic Institute.

ANNEX

This Annex lays down the technical requirements for the performance and operation of cold water meters in order to be imported, placed on the market and put into service, after checks have been carried out. and have imposed the intended marks and signs on them.

The cold water meters, referred to in this provision, are integrative measuring devices that continuously determine the volume of water that passes through them (excluding any other liquid). Said counters include a meter device that drives an indicator device. The water shall be considered to be cold when its temperature ranges from 0 ° C to 30 ° C.

I. Terminology and definitions

1.0 This provision provides for only cold water meters using a direct mechanical procedure, involving volumetric cameras of movable walls or the action of water speed on rotation. of a mobile organ (turbine, propeller, etc.).

1.1 Flow: Q. The flow rate, Q, is the quotient resulting from dividing the volume of water that passes through the meter by the passage time of said volume, expressed in the latter in cubic meters or liters, and the time, in hours, minutes or seconds.

1.2 Supplied Volume: V. -Supplied volume (V), is the total volume of water that has passed through the counter, regardless of the time it took to pass it.

1.3 Maximum flow rate: Q_max-The maximum flow (Q_max) is the highest flow rate at which the counter must operate without deterioration, for limited periods of time, respecting the maximum tolerated errors and without exceed the maximum pressure loss value.

1.4 Nominal flow: Q_n. The nominal flow (Q_n) is equal to half of the maximum flow Q_max. It is expressed in cubic meters per hour, and serves to designate the counter.

At nominal flow (Q_n), the counter must be able to operate under normal use, i.e. continuously and intermittently, without exceeding the maximum tolerated errors.

1.5 Minimum flow: Q_min. The minimum flow rate (Q_min) is the flow rate from which any counter must respect the maximum tolerated errors. It is fixed based on Q_n.

1.6 Measure field.-The measurement field of a water meter is the minimum flow rate (Q_min) and the maximum flow (Q_max), within which the water meter indications must not exceed the maximum errors tolerated. This field is divided into two zones, called lower and higher, in which the maximum tolerated errors are different.

1.7 Transition Flow: Q_t. The transition flow (Q_t) is the flow that separates the lower and upper zones from the measurement field, and where the maximum tolerated errors present a discontinuity.

1.8 Maximum tolerated error. -Maximum tolerated error is the extreme value of the error tolerated by this provision in model approval and in the primitive verification of a water meter.

1.9 Loss of pressure. -For loss of pressure it is necessary to understand what is due to the presence of the water meter in the pipeline.

II. Metrological characteristics

2.1 Maximum tolerated errors:

2.1.1 Measurement errors are indicated as a percentage and are equal to:

Being V_i the value of the volume indicated by the counter and V_a the conventionally true value of the actual volume that passed through the counter, expressed in the same unit and at the same temperature.

2.1.2 The maximum tolerated errors are included in the following table:

Flow

Maximum error tolerated - Percentage
min ≤ Q < Qt	± 5
Qt ≤ Q ≤ Qmax	± 2

In the case that the errors obtained, in the entire measurement field of the counter, are of the same sign, the maximum tolerated errors will be half of those indicated in the table above.

2.2 Metrological classes. -Water meters will be distributed, according to the previously defined Q_min and Q_t values, in three metrological classes, according to the following table:

Classes	Qn
	15 m3/h	3/h
Class A:
valuemin	0.04 Qn	0.08 Qn
t	0.10 Qn	0.30 Qn
Class B:
valuemin	0.02 Qn	0.03 Qn
t	n	0.20 Qn
Class C:
Value of Qmin	0.01 Qn	0.006 Qn
Valuet	0.015 Qn	0.015 Qn

III. Technology features

3.1 Manufacturing. General provisions. -Counters must be manufactured in such a way that:

1. Ensure a prolonged service and exclude the possibility of fraud.

2. Comply with the requirements of this provision, under normal conditions of use.

When the counters are exposed to an accidental reflux of water, they must be able to withstand without deterioration or alteration of their metrological qualities, while recording the recoil produced.

3.2 Materials. The water meter must be manufactured with materials that have adequate resistance and stability to the intended use. The counter must be manufactured with materials that withstand normal internal and external corrosions, and in case of need, shall be protected by the application of appropriate surface treatments.

Water temperature variations, which occur within the field of service temperatures, shall not alter the materials used in their manufacture.

All parts of the water-contact counter must be made with materials that comply with current health legislation and do not cause any degradation of the ability of the water.

3.3 Estanqueness. Resistance to pressure. -Counters must resist, permanently, without any malfunction, leaks or leaks through the walls, or permanent deformation, the continuous pressure of the water for which they are intended, called the maximum service pressure. The minimum value of this pressure will be 10 bar.

Special construction water meters may operate with higher service pressures (see 4.1, f).

3.4 Loss of pressure. -The loss of pressure produced by the counter, including its filter and the part of the conduit integrated in the counter, if available to them, shall be fixed by means of the approval tests Model and no more than 0,25 bar at nominal flow rate and 1 bar at maximum flow rate.

According to the results of the tests, the models shall be distributed in four groups, depending on their loss of pressure to one of the following maximum values: 1, 0,6, 0,3 and 0,1 bar. This value will be entered in the model approval certificate.

3.5 Indicator device.-The indicator device must allow, by means of the simple juxtaposition of the indications of the different elements that constitute it, a safe, easy and unequivocal reading of the volume of water traverses the counter, expressed in cubic meters.

The volume will be given:

a) Well for the position of one or more needles on the circular scales.

b) Well by reading figures aligned consecutively that appear in one or more openings.

c) Well by combining both systems.

In order to be able to distinguish between the multiples and submultiples of the cubic meter, the black color will be used as indicative of the cubic meter and its multiples, and the red color, as indicative of the submultiples of the metro cubic.

The actual or apparent height of the aligned numbers will not be less than 4 millimeters.

In the figures indicators aligned [types b) and c]], the visible offset must be produced from bottom to top in all figures.

The complete advance of a figure in a unit, whatever the order of the unit, must occur while the order figure immediately below runs through the last tenth of its turn. The roller in which the lowest order figures are indicated can be moved continuously in the type c counters.) The whole number of cubic meters must be clearly indicated.

In the needle (types a) and c) indicators, the direction of rotation shall be that of the clock needles. The value, expressed in cubic meters, of the step of each scale must be in the form 10ⁿ, being n an integer, positive, negative or zero, in order to constitute a system of consecutive decades. The indication × 1,000, × 100, × 10, × 1, × 0,1, × 0,01, × 0,001 shall be next to each scale.

In both cases (needles and figures aligned):

You must appear on the dial or immediately next to the encrypted indication, the symbol of the m³unit.

The first indicator element, that is, the one that after a complete turn, indicates the smallest fraction of the cubic meter, must be moved continuously. Its step is called a verification step, this control element can be permanent or can be temporarily materialized by the placement of removable parts, which must not influence the metrological qualities of the counter.

The length of the check step shall not be less than 1 millimetre and not more than 5 millimetres. The scale will consist:

Good of traces of equal thickness, provided that the same does not exceed a quarter of the distance between the axes of two consecutive strokes, without which they distinguish themselves more than their length.

Fine of contrast bands, whose constant width is equal to the length of the step.

3.6 Number of figures and values for the verification step.-The indicator device must be able to record, without returning to zero, a volume, at least equal to the corresponding 1,999 hours of nominal flow operation, expressed in cubic metres.

The verification step must be in the form 1 × 10ⁿ, 2 × 10ⁿ , or 5 × 10ⁿ, where n is an integer, positive, negative, or zero number. It shall be small enough to ensure that, during the verification, a measurement imprecision of not more than 0,5 per 100 can be ensured (a possible reading error of not more than half the length of the smallest step is allowed) and that it is possible to use a minimum flow rate so that the test, performed at this flow rate, does not last longer than one hour and thirty minutes.

A complementary device (star, disc with reference signal, etc.) may be coupled in order to signal the movement of the measuring device, before the displacement of the measuring device is clearly noticeable in the the indicator device.

3.7 Regulatory device. -Counters may include a regulating device that allows to modify the ratio between the indicated volume and the actual volume of liquid that passes through the counter. This device is mandatory for counters that use the water speed action on an item that rotates to perform the measurement.

3.8 Accelerator Device. -Devices that accelerate the counter speed below Q_minare prohibited.

IV. Registrations and marks

4.1 Identification subscriptions.-Any counter shall be compulsorily and indelibly marked, grouped or distributed in the box, the dial of the indicator device or the descriptive plate, the indications following:

a) The name or social reason of the manufacturer or his trademark.

b) The metrological class v the nominal flow Q_n, expressed in cubic meters per hour.

c) The year of manufacture and counter number, unambiguously separated.

d) One or two arrows that indicate the meaning of the flow.

e) The model approval sign or, if any, EEC model approval.

f) The maximum service pressure in bar, in case it is greater than 10 bar.

g) The letter V or H, if the counter can only function correctly in a vertical position (V) or in a horizontal position (H).

4.2 Site of verification marks.-A site must be provided on an essential part (in principle the casing), visible without disassembly, to place the check marks.

4.3 Precinct. -Counters must carry protective devices that can be sealed in order to prevent, both before and after the correct installation of the counter, the disassembly or modification of the counter or of its regulatory device, without deterioration of such devices.

V. Model Approval

5.1 Procedure. The model approval procedure will be performed in accordance with the Royal Decrees 597/1988 of 10 June or 1616/1985 of 11 September, as the case may be.

5.2 Tests for model approval. -Once it has been established, in accordance with the file of the application for approval, that the model complies with the requirements of this provision, they shall be tested for laboratory a certain number of devices under the following conditions:

5.2.1 Number of counters to be tested. The petitioner must initially make available to the Spanish Metrology Center the number of counters set in the following table:

Nominal flow Qn in m3/h		Number of
n ≤	5	10
5 < Qn ≤	50	6
50 < Qn ≤	1000	2
Qn	1000	1

The Spanish Metrology Centre, according to the course of the tests, may require additional copies for these tests.

5.2.2 Pressure. -For metrological tests (paragraph 5.2.4) the pressure at the outlet of the counter must be sufficient to prevent cavitation.

5.2.3 Test Material. -In general, the counters will be tested individually and, in any case, so that the individual characteristics of each one of them are clearly visible.

The Spanish Metrology Centre will take the necessary steps to ensure that, taking into account the different causes of error of the installation, the maximum uncertainty of relative accuracy is 0.2 per 100 volume supplied.

The maximum relative accuracy of the installation shall be 5 per 100 in the measurement of the pressure and of the 2.5 to the extent of the pressure loss.

The relative variation of the value of the flow rates, during each test, must not exceed 2.5 per 100 between Q_min and Q_t and 5 per 100 between Q_t and Q_max.

Whatever the place in which the tests are carried out, the installation must be approved by the Spanish Metrology Center.

5.2.4 Execution of the tests. -These tests comprise the following operations, carried out in the order shown:

1. Watertight tests.

2. Determination of the error curves according to the flow rate, studying the influence of the pressure and taking into account the conditions of installation (lengths of straight pipe, before and after the counter: Bottlenecks, obstacles, etc., provided by the manufacturer for this type of counter.

3. Determination of the pressure losses.

4. Accelerated ageing study.

The study of tightness includes the following two trials:

(a) Each counter must bear, without leakage, without oozing through the walls and without deterioration, a test pressure equal to 16 bar or 1,6 times the maximum service pressure, applied for 15 minutes (point 4.1 (f)).

(b) Each counter must bear no destruction, no lock, a pressure equal to 20 bar or twice the maximum service pressure, applied for one minute [see point 4.1 (f)].

The results of tests 2 and 3 must provide a sufficient number of points to accurately plot the curves throughout the measurement field.

The accelerated aging study will be performed under the following conditions:

	nominal Qn in m3/h	Flow trial	Nature of the trial	Number of interrupts	Duration of stops in seconds	Operating duration with the test flow	Duration of phases acceleration and braking in seconds
Qn ≤ 10	Qn	Discontinuous.	100,000	15	15 seconds.	0.15 (Qn) * seconds with a minimum of one second.
	2 Qn								100 hours.
n	Qn	Continuous.			800 hours.
	2 Qn	Continuous.			200 hours.

* (Q_n) Is a number equal to the value of Q_n expressed in m³/h.

Before the first test and after each series of tests, the measurement errors shall be determined, at least in the following flow rates:

Q_min -Q_t -0.3 Q_n -0.5 Q_n -1 Q_n -2 Q_n

In each test, the volume provided shall be sufficient to allow the needle or the roll of the verification step to complete one or more complete turns and the effects of the cyclic distortion to be suppressed.

5.2.5 Model Approval Conditions. -Water counter model will be approved:

(a) When complying with the administrative, technical and metrological requirements of this provision.

(b) When tests 1, 2 and 3 as provided for in paragraph 5.2.4., it is clear that the counter complies with the metrological and technological characteristics of Parts II and III of this Annex.

c) When, after each accelerated aging test:

1. Do not produce, in relation to the initial curve, measurement variations greater than 1,5 per 100 between Q_t and Q_max, both inclusive, not greater than 3 per 100 between Q_min, inclusive, and Q_t, inclusive.

2. And that the counter error is maximum of ± 6 per 100 between Q_min, inclusive, and Q_t, exclusive and ± 2.5 per 100 between Q_t and Q_max, both inclusive.

5.3 Model Approval Certificate. The model approval certificate will collect the placement of the mandatory signs and marks and the seals that must prevent the disassembly, even partial of the counter.

VI. Primitive Verification

Any cold water meter, whose model has been approved, will be subjected to the primitive verification. The conformity with an approved model of the counters presented for the primitive verification can be checked, previously examining the different parts in the course of manufacture and assembly, or disarming a counter of the ones that are presented. The site of the primitive verification will be authorized by the Spanish Metrology Center. The layout of the premises and the material of the tests shall be such as to enable the verification to be carried out accurately and safely. The requirements of paragraph 5.2.3 shall be complied with; however, the water meters of the same model and size may be placed in series, provided that the pressure at the exit of all the counters is sufficient for them not to exist. disturbances in operation or interference between the counters.

The installation may include automatic devices, derivations, section reductions, etc., provided that each test circuit between counters to be verified and control tanks is clearly defined and that, in all time, its tightness can be verified.

Any water supply system is authorised, but in the case of several parallel test circuits, no interactions with the provisions of paragraph 5.2.3. shall occur between them.

If a control tank is divided into several chambers, the rigidity of the separation partitions shall be sufficient to ensure that the volume of a chamber does not vary more than 0,2 per 100 depending on the full size of the adjacent chambers. or empty.

The verification includes a precision test to be carried out at least three flow rates, respectively:

a) Between 0.9 Q_max and Q_max.

b) Between Q_t and 1.1 Q_t.

c) Between Q_min and 1.1 Q_min.

By the first of these tests, the pressure loss that must be less than the value indicated in the model approval certificate shall be observed.

The maximum tolerated errors are as shown in point 2.1.

In each test, the volume provided shall be such that the needle or the roll of the check step performs one or more complete turns and the effects of the cyclic distortion are removed.

When all errors are of the same sign, the counter must be adjusted so that none of the errors exceed half of the maximum tolerated error.

To the counters that have successfully passed the tests of the primitive verification, the corresponding mark and the seals provided for in paragraph 4.3 shall be placed.