Uniform approach to metering

The Open Metering System initiative of the manufacturers associations figawa, KNX and ZVEI has published an open, manufacturer independent, interoperable device and interface definition called an Open Metering System Specification.

The Open Metering System (OMS) is Europe’s only system definition representing a uniform approach for all media (electricity, gas, heat and water, including sub-metering). At present, the OMS specifications are being reviewed by the European Committee for Standardisation (CEN) as European new work item proposal TC 294. The OMS specification is available on the internet at www.openmetering.org.

From May 2007, several working groups of the Open Metering initiative checked the use of existing standards and defined supplements or concretions where necessary. For the data transfer between the actual meters and the data concentrator MUC – defined as primary communication – the EN 13757 standard was identified as the only current standard applicable to metering devices. This standard defines the M-Bus as a physical interface (wired and wireless), as well as a data protocol. EN 13757 also complies with the KNX standard.

The remote communication is defined by approved internet standards, with transfer either directly via a DSL hook-up in the building, via mobile phone networks such as GPRS, or via PLC technology on the power distribution line.

For detailed visualisation (consumption visualisation), connection of the building automation system at the end customer, and for future services such as tariff and load management, the widespread KNX standard (ISO/IEC 14543) applies.

While working on the specification, international interests were also respected, since future smart metering functionality must be harmonised all over Europe. To reach this goal, cooperation with KEMA was established to harmonise the specification with the Dutch rules NTA 8130/DSMR.

As an important topic for enabling the acceptance of intelligent metering systems, the requirements of data security and data access management were also taken into account.

The Open Metering System Group has already initiated the next steps for the implementation of the standard: a neutral body will soon define a binding certification system to ensure the compatibility of all devices in practice, as defined in the OMS specification.