New EN1359 norm for diaphragm gas meters

Very soon, a new version of the European EN1359 standard for diaphragm gas meters will be issued. Several manufacturers already have approached us, eager to learn what to expect. These are the main changes compared to the current version at a glance:

  1. A new accelerated durability test will be added to the testing program. The current version of the EN1359 standard prescribes an endurance test during which diaphragm gas meters are subjected to a continuous high gas flow for 5000 hours, or 7 months. During this period, our test engineers check whether a meter still performs well when Qmax flows pass through. For meters up till 10 m3/h this endurance test has been replaced by a more realistic, time-saving alternative of 2000 hours – 3 months. Testing will now be conducted at various flow rates. This is more consistent with the actual use of diaphragm gas meters: outside of the lab, more or less gas will flow through at different moments. The time of testing can be shortened since the variable gas flows put more stress on the meters. NMi has invested in a new endurance test facility which ensures premium testing services for our customers as soon as the modified norm will come into force.
  2. Temperature tests will be performed over the whole flow rate range. According to the new EN1359 these have to be carried out at Qmin as well.

Next to these adjustments, some other testing details will change as well. However, the above two points are the most salient. For more information, please contact Henri Schouten: hschouten@nmi.nl

Henri Schouten

Henri Schouten

Business Development Manager Utilities, Worldwide

Expert for all utility residential meters (electricity/ gas/ water/ heat). Member/ chairman of multiple IEC, CENELEC, OIML and WELMEC groups. Chairman of the Dutch mirrorgroup NEC13. One of the writers of OIML R137.