Overview
IEC 62056-7-3:2017 defines DLMS/COSEM communication profiles for wired and wireless M‑Bus in local and neighbourhood networks. It specifies how the COSEM data model and the DLMS/COSEM application layer are mapped onto M‑Bus lower layers (physical, link, transport) and is intended for smart metering and related devices (meters, in‑home displays, home automation nodes). The standard references the EN 13757 series for the M‑Bus lower layers and follows the DLMS/COSEM suite rules in IEC 62056‑5‑3 and IEC 62056‑1‑0.
Key topics and technical requirements
- Scope and purpose: Profiles are limited to protocol usage in conjunction with the COSEM data model and DLMS/COSEM application layer; network management and M‑Bus device configuration are out of scope.
- Layer mapping: Guidance on using the physical, link and transport layers of wired and wireless M‑Bus with DLMS/COSEM.
- Service primitives and protocol behavior: Definition of MBUS‑DATA service primitives and the M‑Bus DATA protocol mapping for DLMS/COSEM exchanges.
- Addressing and identification: Schemes for link‑layer and transport‑layer addressing, broadcast handling, and an application addressing extension (M‑Bus wrapper).
- Association and session management: ACSE services for application association establishment/release and xDLMS service support for request/response, unsolicited, and broadcast messages.
- Security and long messages: Notes on DLMS/COSEM security mechanisms and transporting long application messages over M‑Bus.
- Media considerations: Timing, bandwidth, and media access constraints for local/neighbourhood M‑Bus deployments.
- Annexes and implementations: Informative annexes with M‑Bus frame structures, encoding examples (e.g., daily billing data), new COSEM interface classes for M‑Bus, and message sequence charts.
Practical applications and who uses this standard
IEC 62056‑7‑3 is applied where DLMS/COSEM interoperates with M‑Bus networks:
- Utilities and metering service providers deploying smart metering in neighbourhood and building networks.
- Meter manufacturers and module vendors implementing DLMS/COSEM over wired or wireless M‑Bus.
- System integrators and firmware developers integrating COSEM data models with EN 13757 M‑Bus stacks.
- Test laboratories, certification bodies, and solution architects validating interoperability of meters, in‑home displays, and gateway devices.
Related standards
- IEC 62056‑1‑0 (DLMS/COSEM suite framework)
- IEC 62056‑5‑3 (rules for communication profiles)
- EN 13757 series (M‑Bus physical/link/transport specifications)
- DLMS User Association resources for conformance and maintenance
By aligning DLMS/COSEM application semantics with M‑Bus transport profiles, IEC 62056‑7‑3 enables standardized, interoperable electricity metering data exchange across local and neighbourhood M‑Bus deployments.