DLMS USER ASSOCIATION – Blue Book Edition 9.0: focus on smart metering and gas metering


One of the key activities of the DLMS UA is to identify new applications and requirements as well as to maintain and develop the DLMS/COSEM specification so that these new requirements can be met. This activity is of particular importance with the growing use of IEC 62056 / EN 13757-1 DLMS/COSEM in smart metering systems and for gas metering.

DLMS/COSEM, the language of interoperable metering is particularly suitable to discuss these requirements, to come to a common understanding on them and to precisely formulate them on the language of the standard, so that interoperability is ensured.

In the past year, utilities and vendors, participants of important projects, have been working closely in the working groups of the DLMS UA to achieve this objective. The results of the work are published in the new Edition 9.0 of the Blue Book and include, among others, the following:

  • the Limiter interface class, allowing to monitor the load of each customer in customer groups against normal and emergency thresholds, allowing a “soft” load control, i.e. limitation instead of complete switch off;
  • the Disconnector interface class, allowing to disconnect and reconnect supply to the premises, locally or remotely, depending on various conditions, like load, voltage, payment etc.;
  • the Image transfer interface class, allowing to manage the download, validation and activation of new, approved firmware to the meter, so that its functions can be kept up to date;
  • new M-BUS related interface classes, allowing to set up and manage data exchange via M-Bus (specified in EN 13757). In a typical system architecture, the electricity meter or an in-house multi-utility concentrator would exchange data with a data collection system using DLMS/COSEM on the one hand and with other utility meters using M-BUS on the other hand;
  • new versions of the Association interface classes and a new Security setup class, managing data transport security, allowing to apply cryptographic protection to the messages to be sent and to check and remove that protection on the messages received. This ensures confidentiality and authenticity of important messages. The selected algorithm uses the Advanced Encryption Standard (AES) with 128 bit keys, in the Galois-Counter Mode (GCM), particularly suitable for implementing on microcontrollers;
  • new interface classes set up and manage data exchange over power lines, using the S-FSK PLC technology, as specified in the IEC 61334 series;
  • new OBIS codes to manage events and alarms, for example to detect fraudulent attempts and raise alarms when selected events occur;
  • new OBIS codes to manage providing the end customer with information, a cornerstone of any smart metering system; – new OBIS codes to manage the complex process of gas volume conversion and energy conversion, gas composition analysis and process control.

The new Blue Book is immediately available to all members of the DLMS UA, and the implementation of the new features is well underway. Excerpts of the DLMS UA Coloured Books are publicly available.

In line with the open standards policy of the DLMS UA, the new elements have been offered for international standardisation to the IEC, the International Electrotechnical Commission, and to the CEN, the European Committee for Standardisation. As the bulk of the technical work has been already done by the DLMS UA, a “fast track” standardisation process can be used. This will lead to a new edition of the relevant parts of the IEC 62056 / EN 13757 series.

Please contact us for more information or any question about the DLMS User Association at Pre-de-la-Fontaine 19, CH-1217 Meyrin-Geneva, Switzerland, e-mail: dlms@dlms.com, or visit our website www.dlms.com.

Gyõzõ Kmethy, President
Paul Fuchs, General Secretary