Can I See Some Practical Examples For IEC 61508?

Modified on Sun, 11 May, 2025 at 10:14 PM

The range of E/E/PE safety-related systems to which IEC 61508 can be applied includes:

emergency shut-down systems,
fire and gas systems,
turbine control,
gas burner management,
crane automatic safe-load indicators,
guard interlocking and emergency stopping systems for machinery,
medical devices,
dynamic positioning (control of a ship's movement when in proximity to an offshore installation),
fly-by-wire operation of aircraft flight control surfaces,
railway signalling systems (including moving block train signalling),
variable speed motor drives used to restrict speed as a means of protection,
automobile indicator lights, anti-lock braking and engine-management systems,
remote monitoring, operation or programming of a network-enabled process plant,
an information-based decision support tool where erroneous results affect safety.

Relevant means of implementing safety functions include electro-mechanical relays (i.e. electrical), non-programmable solid-state electronics (i.e. electronic) and programmable electronics. Programmable electronic safety-related systems typically incorporate programmable controllers, programmable logic controllers, microprocessors, application specific integrated circuits, or other programmable devices (for example “smart” sensors, transmitters and actuators).

In every case, the standard applies to the entire E/E/PE safety-related system (for example from sensor, through control logic and communication systems, to final actuator, including any critical actions of a human operator). For safety functions to be effectively specified and implemented, it is essential to consider the system as a whole.

This text contains extracts from the IEC Functional Safety Zone. All such extracts are copyright of International Electrotechnical Commission © 2005, IEC, Geneva, Switzerland. All rights reserved. IEC has no responsibility for the placement and context in which the extracts are reproduced. This notice takes precedence over any general copyright statement.