BS EN 50491-3:2009

Introduction
1 Scope
2 Normative references
3 Definitions and abbreviations
4 Classification of HBES/BACS network interfaces
5 Safety requirements and compliance criteria
Annex A (normative) - Special national conditions
Bibliography

Defines the electrical safety requirements for all devices connected to HBES/BACS.

This European Standard provides the electrical safety requirements for all devices connected to HBES/BACS.

This European Standard is applicable to

• operator stations and other human system interface devices,

• devices for management functions,

• control devices, automation stations and application specific controllers,

• field devices,

• cabling and interconnection of devices.

This European Standard covers the following requirements and compliance criteria:

• protection from hazards in the device;

• protection from overvoltages on the network;

• protection from touch current;

• protection from hazards caused by different type of circuits;

• protection of the communication wiring from overheating caused by excessive current.