NBN EN 50470-2 : 2007

1 Scope
2 Normative references
3 Terms, definitions and abbreviations
4 Standard electrical values
5 Mechanical requirements
   5.1 General
   5.2 Register (counting mechanism)
   5.3 Direction of rotation and marking of the rotor
6 Climatic conditions
7 Electrical requirements
   7.1 Power consumption
       7.1.1 Measuring method
       7.1.2 Voltage circuits
       7.1.3 Current circuits
   7.2 AC voltage test
8 Accuracy requirements and tests
   8.1 Limits of percentage error due to variation of the load
   8.2 Repeatability
   8.3 Limits of additional percentage error due to influence
       quantities
   8.4 Maximum permissible error (MPE)
   8.5 Effect of disturbances of long duration
   8.6 Short time overcurrents
   8.7 Performing the tests
       8.7.1 Accuracy test conditions
       8.7.2 Accuracy test at reference conditions
       8.7.3 Interpretation of accuracy test results
       8.7.4 Repeatability
       8.7.5 Test of effects of influence quantities
       8.7.6 Calculation of the composite error
       8.7.7 Test of effects of disturbances of long duration
       8.7.8 Short time overcurrents
       8.7.9 Test of starting and no-load condition
       8.7.10 Meter constant
       8.7.11 Adjustment
9 Durability
10 Reliability
11 Protection against corruption
Annex A (informative) Calculation of the composite error
Annex B (normative) Test circuit diagram for the test of
                       immunity to earth fault
Annex ZZ (informative) Coverage of Essential Requirements of
                       EC Directives
Bibliography

Applies to newly manufactured electromechanical watt-hour meters intended for residential, commercial and light industrial use, of class indexes A and B, for the measurement of alternating current electrical active energy in 50 Hz networks.