NBN EN 12405 : 2002

Foreword
1 Scope
2 Normative references
3 Terms, definitions and symbols
    3.1 Terms and definitions
    3.2 Symbols
4 Principle of measurement
    4.1 Conversion as a function of temperature
    4.2 Conversion as a function of pressure and
          temperature
    4.3 Conversion as a function of pressure, temperature
          and deviation from the ideal gas law
    4.4 Correction of the volume at measurement conditions
5 Rated operating conditions
    5.1 Specified field of measurement
          5.1.1 Specified measurement range for gas
                  pressure
          5.1.2 Specified measurement range for gas
                  temperature
          5.1.3 Gas characteristics
    5.2 Environmental class
          5.2.1 Ambient temperature range
          5.2.2 Humidity range
    5.3 Power supply
6 Construction requirements
    6.1 General
    6.2 Casings
    6.3 Indications
          6.3.1 General
          6.3.2 Electronic indicating device
    6.4 Inputs for volume conversion
    6.5 Battery powered conversion device
    6.6 Security devices and alarms
7 Installation requirements
    7.1 General
    7.2 Temperature transducer
    7.3 Pressure transducer
8 Performance
    8.1 Reference conditions
    8.2 Rated operating conditions
    8.3 Maximum permissible errors
          8.3.1 Error of conversion
          8.3.2 Specific errors for a gas-volume conversion
                  device, type 2
    8.4 Influence factors
    8.5 Disturbances
    8.6 Durability
9 Tests of conformity
    9.1 Test conditions
    9.2 Tests and their classification
    9.3 Sample of gas volume conversion device required
          for testing
    9.4 Test report
10 Marking
Annex A (normative) Type test
    A.1 General conditions
    A.2 Accuracy tests under reference conditions
    A.3 Effect of ambient temperature
    A.4 Effect of damp heat, steady state test
    A.5 Effect of damp heat, cyclic test
    A.6 Electrical power variation
    A.7 Short time power interruption
    A.8 Electrical bursts
    A.9 Electromagnetic immunity
    A.10 Electrostatic discharges
    A.11 Effect of an overload of pressure
    A.12 Mechanical resistance to overload of pressure
    A.13 Effect of vibrations
    A.14 Effect of shocks
    A.15 Durability
Annex B (informative) Model type test report
    B.1 General
    B.2 Accuracy tests under reference conditions
    B.3 Ambient temperature
    B.4 Effect of damp heat, steady state test
    B.5 Effect of damp heat, cyclic test
    B.6 Electrical power variation
    B.7 Short time power interruption
    B.8 Electrical bursts
    B.9 Electromagnetic immunity
    B.10 Electrostatic discharges
    B.11 Effect of an overload of static pressure
    B.12 Mechanical resistance to overload of pressure
    B.13 Effect of vibrations
    B.14 Effect of shocks
    B.15 Durability
Bibliography

Defines the requirements and tests for the construction, performance, safety and conformity of gas-volume electronic conversion devices associated to gas meters, used to measure volumes of fuel gases of the 1st and 2nd families according to EN 437.