IEC 61131-5-2000 PDF

Full title and description

Programmable controllers - Part 5: Communications (IEC 61131-5:2000). This part of IEC 61131 specifies the communication aspects of a programmable controller (PLC), describing the behavior of a PLC when acting as a server and as a client, the services offered and requested, and how PLC communication functionality maps onto underlying communication systems and networks.

Abstract

IEC 61131-5:2000 defines a communication model and service set for programmable controllers to enable interoperable data access and message exchange between PLCs and other devices or applications. It focuses on the PLC viewpoint (client/server roles), service semantics, and includes annexes that show mappings to selected communication systems. The part is intended to be read together with other parts of the IEC 61131 series.

General information

• Status: International standard — published and in stable status (stability date noted by publisher).
• Publication date: 15 November 2000.
• Publisher: International Electrotechnical Commission (IEC).
• ICS / categories: 25.040.40; 35.240.50.
• Edition / version: Edition 1.0 (2000).
• Number of pages: 203 (as listed by the IEC publication entry).

Scope

The standard specifies communication requirements from the perspective of the programmable controller: how external devices may communicate with a PLC acting as a server, and how a PLC application may request services from other devices. It does not aim to standardize arbitrary device-to-device communications when a PLC is used only as a gateway; rather, it defines the PLC’s client/server behavior and provides mappings to particular communication systems in informative or normative annexes. The European adoption as EN 61131-5:2001 endorses the IEC text without modification.

Key topics and requirements

• Client/server communication model for programmable controllers and associated service definitions.
• Specification of services a PLC provides and services a PLC can request (data access, messaging, connection management).
• Behavioral definitions independent of a specific underlying communications technology, with mapping guidance to selected networks/fieldbuses in annexes.
• Normative and informative annexes illustrating protocol mappings and implementation considerations.
• Conformance considerations for PLC vendors and system integrators to ensure interoperable communications.

Typical use and users

Primary users include PLC and automation equipment manufacturers, control-system engineers, system integrators, industrial software vendors, and testing/conformity bodies. The standard is used when designing PLC communication stacks, implementing PLC-to-device interfaces, and verifying interoperability in industrial automation domains such as process control, water-management systems, and building or municipal automation.

Related standards

IEC 61131-5 is one part of the IEC 61131 family for programmable controllers; other parts cover general information, equipment specifications and tests, programming languages, user guidelines, functional safety, fuzzy control programming, implementation guidance, and newer parts for digital interfaces and XML exchange formats. IEC 61131-5 was adopted as EN 61131-5:2001 in Europe; the part is commonly referenced alongside IEC 61131-1, -2, -3 and the remaining series parts when specifying PLC systems.

Keywords

programmable controller; PLC; communications; client-server; services; protocol mapping; industrial automation; fieldbus; data access; interoperability.

FAQ

Q: What is this standard?

A: IEC 61131-5:2000 is Part 5 of the IEC 61131 family and defines communications for programmable controllers — the service model, behaviors for PLCs acting as servers and clients, and mappings to communication systems.

Q: What does it cover?

A: It covers the communication semantics and service definitions from the PLC viewpoint (data access, messaging, connection management), plus annex material that maps the specified behavior to particular communication technologies. It is intended to ensure interoperable PLC communications rather than to mandate a single network technology.

Q: Who typically uses it?

A: PLC manufacturers, control-system engineers, integrators, industrial software developers, and conformity testing organizations use it when designing, implementing, or validating PLC communication functions.

Q: Is it current or superseded?

A: IEC 61131-5:2000 remains the published Part 5 edition originating in 2000; publisher metadata indicates a stability horizon (publisher-stated date) for the publication entry. Users should check the IEC catalogue or national adoption bodies for any amendments, corrigenda, or newer replacements before relying on it for new projects.

Q: Is it part of a series?

A: Yes — it is part of the IEC 61131 series (Programmable controllers). The series includes Parts 1–10 (and technical reports) covering general information, hardware specifications, programming languages, user guidance, safety, communication, and related topics; Part 5 is the communications-focused part.

Q: What are the key keywords?

A: Programmable controller, PLC, communications, client/server, protocol mapping, fieldbus, interoperability, data access, industrial automation.