Directive 2014/32/EU of the European Parliament and of the CouncilDangos y teitl llawn

ANNEX IV U.K.

GAS METERS AND VOLUME CONVERSION DEVICES (MI-002) U.K.

The relevant requirements of Annex I, the specific requirements of this Annex and the conformity assessment procedures listed in this Annex, apply to gas meters and volume conversion devices defined below, intended for residential, commercial and light industrial use.

DEFINITIONS U.K.

Gas meter	An instrument designed to measure, memorise and display the quantity of fuel gas (volume or mass) that has passed it.
Conversion device	A device fitted to a gas meter that automatically converts the quantity measured at metering conditions into a quantity at base conditions.
Minimum flowrate (Qmin)	The lowest flowrate at which the gas meter provides indications that satisfy the requirements regarding maximum permissible error (MPE).
Maximum flowrate (Qmax)	The highest flowrate at which the gas meter provides indications that satisfy the requirements regarding MPE.
Transitional flowrate (Qt)	The transitional flowrate is the flowrate occurring between the maximum and minimum flowrates at which the flowrate range is divided into two zones, the ‘upper zone’ and the ‘lower zone’. Each zone has a characteristic MPE.
Overload Flowrate (Qr)	The overload flowrate is the highest flowrate at which the meter operates for a short period of time without deteriorating.
Base conditions	The specified conditions to which the measured quantity of fluid is converted.

PART I U.K. SPECIFIC REQUIREMENTSGAS METERS

1. Rated operating conditions U.K.

The manufacturer shall specify the rated operating conditions of the gas meter, taking into account:

1.1. The flowrate range of the gas shall fulfil at least the following conditions: U.K.

Class	Qmax/Qmin	Qmax/Qt	Qr/Qmax
1,5	≥ 150	≥ 10	1,2
1,0	≥ 20	≥ 5	1,2

1.2. The temperature range of the gas, with a minimum range of 40 °C. U.K.

1.3. The fuel/gas related conditions U.K.

The gas meter shall be designed for the range of gases and supply pressures of the country of destination. In particular the manufacturer shall indicate:

• the gas family or group;

• the maximum operating pressure.

1.4. A minimum temperature range of 50 °C for the climatic environment. U.K.

1.5. The nominal value of the AC voltage supply and/or the limits of DC supply. U.K.

2. Maximum permissible error (MPEs) U.K.

2.1. Gas meter indicating the volume at metering conditions or mass U.K.

Table 1

Class	1,5	1,0
Qmin ≤ Q < Qt	3 %	2 %
Qt ≤ Q ≤ Qmax	1,5 %	1 %

The gas meter shall not exploit the MPEs or systematically favour any party.

2.2. For a gas meter with temperature conversion, which only indicates the converted volume, the MPE of the meter is increased by 0,5 % in a range of 30 °C extending symmetrically around the temperature specified by the manufacturer that lies between 15 °C and 25 °C. Outside this range, an additional increase of 0,5 % is permitted in each interval of 10 °C. U.K.

3. Permissible effect of disturbances U.K.

3.1. Electromagnetic immunity U.K.

3.1.1. The effect of an electromagnetic disturbance on a gas meter or volume conversion device shall be such that: U.K.

• the change in the measurement result is no greater than the critical change value as defined in point 3.1.3, or

• the indication of the measurement result is such that it cannot be interpreted as a valid result, such as a momentary variation that cannot be interpreted, memorised or transmitted as a measuring result.

3.1.2. After undergoing a disturbance, the gas meter shall: U.K.

• recover to operate within MPE, and

• have all measurement functions safeguarded, and

• allow recovery of all measurement data present just before the disturbance.

3.1.3. The critical change value is the smaller of the two following values: U.K.

• the quantity corresponding to half of the magnitude of the MPE in the upper zone on the measured volume;

• the quantity corresponding to the MPE on the quantity corresponding to one minute at maximum flowrate.

3.2. Effect of upstream-downstream flow disturbances U.K.

Under installation conditions specified by the manufacturer, the effect of the flow disturbances shall not exceed one third of the MPE.

4. Durability U.K.

After an appropriate test, taking into account the period of time estimated by the manufacturer, has been performed, the following criteria shall be satisfied:

4.1. Class 1,5 $3 U.K.

4.1.1. The variation of the measurement result after the durability test when compared with the initial measurement result for the flow rates in the range Q_t to Q_max- shall not exceed the measurement result by more than 2 %. U.K.

4.1.2. The error of indication after the durability test shall not exceed twice the MPE in point 2. U.K.

4.2. Class 1,0 $3 U.K.

4.2.1. The variation of the measurement result after the durability test when compared with the initial measurement result shall not exceed one-third of the MPE in point 2. U.K.

4.2.2. The error of indication after the durability test shall not exceed the MPE in point 2. U.K.

5. Suitability U.K.

5.1. A gas meter powered from the mains (AC or DC) shall be provided with an emergency power supply device or other means to ensure, during a failure of the principal power source, that all measuring functions are safeguarded. U.K.

5.2. A dedicated power source shall have a lifetime of at least five years. After 90 % of its lifetime an appropriate warning shall be shown. U.K.

5.3. An indicating device shall have a sufficient number of digits to ensure that the quantity passed during 8 000 hours at Q_max does not return the digits to their initial values. U.K.

5.4. The gas meter shall be able to be installed to operate in any position declared by the manufacturer in its installation instruction. U.K.

5.5. The gas meter shall have a test element, which shall enable tests to be carried out in a reasonable time. U.K.

5.6. The gas meter shall respect the MPE in any flow direction or only in one flow direction clearly marked. U.K.

6. Units U.K.

Metered quantity shall be displayed in cubic metre, or in kilogram.

PART II U.K. SPECIFIC REQUIREMENTSVOLUME CONVERSION DEVICES

A volume conversion device constitutes a sub-assembly when it is together with a measuring instrument with which it is compatible.

For a volume conversion device, the essential requirements for the gas meter shall apply, if applicable. In addition, the following requirements shall apply:

7. Base conditions for converted quantities U.K.

The manufacturer shall specify the base conditions for converted quantities.

8. MPE U.K.

• 0,5 % at ambient temperature 20 °C ± 3 °C, ambient humidity 60 % ± 15 %, nominal values for power supply;

• 0,7 % for temperature conversion devices at rated operating conditions;

• 1 % for other conversion devices at rated operating conditions.

Note: U.K.

The error of the gas meter is not taken into account. U.K.

The volume conversion device shall not exploit the MPEs or systematically favour any party. U.K.

9. Suitability U.K.

9.1. An electronic conversion device shall be capable of detecting when it is operating outside the operating range(s) stated by the manufacturer for parameters that are relevant for measurement accuracy. In such a case, the conversion device must stop integrating the converted quantity, and may totalise separately the converted quantity for the time it is operating outside the operating range(s). U.K.

9.2. An electronic conversion device shall be capable to display all relevant data for the measurement without additional equipment. U.K.

PART III U.K. PUTTING INTO USE AND CONFORMITY ASSESSMENT

Putting into use U.K.

10.

(a)

Where a Member State imposes measurement of residential use, it shall allow such measurement to be performed by means of any Class 1,5 $3, and by Class 1,0 $3 which have a Q_max/Q_min ratio equal or greater than 150.

(b)

Where a Member State imposes measurement of commercial and/or light industrial use, it shall allow such measurement to be performed by any Class 1,5 USD 3.

(c)

As regards the requirements under points 1.2 and 1.3, Member States shall ensure that the properties be determined by the utility or the person legally designated for installing the meter, so that the meter is appropriate for the accurate measurement of consumption that is foreseen or foreseeable.

CONFORMITY ASSESSMENT U.K.

The conformity assessment procedures referred to in Article 17 that the manufacturer can choose between are

B + F or B + D or H1.