IEC 62056

IEC 62056

IEC62056 is a set of standards for Electricity metering – Data exchange for meter reading, tariff and load control by International Electrotechnical Commission. The IEC62056 standards are the International Standard versions of the DLMS/COSEM specification. DLMS or Device Language Message Specification (originally Distribution Line Message Specification), is the suite of standards developed and maintained by the DLMS User Association and has been co-opted by the IEC TC13 WG14 into the IEC 62056 series of standards. The DLMS User Association has established a D Type liaison with IEC TC13 WG14 responsible for international standards for meter data exchange and establishing the IEC 62056 series. In this role, the DLMS UA provides maintenance, registration and conformance testing services for IEC 62056 DLMS/COSEM. COSEM or Companion Specification for Energy Metering, includes a set of specifications that defines the Transport and Application Layers of the DLMS protocol. The DLMS User Association defines the protocols into a set of four specification documents namely Green Book, Yellow Book, Blue Book and White Book. The Blue book describes the COSEM meter object model and the object identification system, the Green book describes the Architecture and Protocols, the Yellow book treats all the questions concerning conformance testing, the White book contains the glossary of terms. If a product conforms to DLMS Yellow Book then it automatically implies conformance to IEC62056 set of standards.

The IEC TC13 WG 14 groups the DLMS specifications under the common heading: "Electricity metering - Data exchange for meter reading, tariff and load control". DLMS protocol suite is not specific to electricity metering.

• IEC 62056-21: Direct local data exchange (3d edition of IEC 61107) describes how to use COSEM over a local port (optical or current loop)
• IEC 62056-42: Physical layer services and procedures for connection-oriented asynchronous data exchange
• IEC 62056-46: Data link layer using HDLC protocol
• IEC 62056-47: COSEM transport layers for IPv4 networks
• IEC 62056-53: COSEM Application layer
• IEC 62056-61: Object identification system (OBIS)
• IEC 62056-62: Interface classes