Functional safety

What is functional safety?

The European Parliament’s Machinery Directive 2006/42/EC ensures compliance with a range of legal regulations, including functional safety, for equipment and systems. The goal is to minimize risks to people, the environment, and capital assets through systematic error prevention, error detection, and, in particular, error control.

All equipment and systems that, in the event of a failure, could result in death or injury to people, catastrophic damage to the environment, or the destruction of, for example, production facilities, must be classified as “safety-critical.” The relevant safety standards must be applied accordingly during the design, development, manufacture, and operation of such equipment and systems.

What does the term "functional safety" encompass?

Functional safety, also abbreviated as FuSi, encompasses the aspect of overall safety that depends on the correct operation of electrical, electronic, or programmable systems. Its purpose is to reduce risks arising from malfunctions to an acceptable level throughout the entire lifecycle.

Functional safety ensures that safety functions operate reliably, for example, by transitioning to safe states in the event of a failure. The concept thus ensures systematic risk management. This also includes the analysis of failure probabilities and the prevention of systematic errors.

Functional Safety: Core Process

• Identify hazards and assess risks (e.g., using FMEA).
• Define safety functions using parameters such as PL/SIL (Performance Level/Safety Integrity Level), fault tolerance time, or other thresholds.
• Review the system design, select components, and prepare documentation.

Why functional safety?

The concept of functional safety enables the early identification of hazards through analyses such as FMEA (Failure Mode and Effects Analysis) or HARA (Hazard Analysis and Risk Assessment). It also implements safety functions with defined integrity levels (e.g., PL).

There are specific standards—such as ISO 13849, IEC 62061, IEC 61508, and ISO 26262—that define requirements for functional safety. Adhering to these standards is necessary to comply with legal requirements, reduce liability risks, and enable product certification.
Electronic, wear-free systems also help minimize random failures, thereby increasing system availability and service life.

Functional safety—commonly referred to internationally as "functional safety"—is applied across various industries. In accordance with the state of the art, it ensures safe shutdown functions and controlled fail-safe behavior, and supports safety-critical assistance systems, such as braking or steering systems in vehicles.

Here is an overview of the affected industries and specific applications:

Mechanical engineering: Emergency stop circuits that bring machines to an immediate halt; light curtains that automatically deactivate when interrupted; fail-safe controls for presses that switch to a safe state in the event of sensor failures; speed monitoring on conveyor belts; safety gates with position sensors.

Process industry: Emergency shut-off valves in chemical plants in case of pressure surges; temperature monitoring in reactors with automatic cooling; level control in tanks to prevent overflows; gas detectors with evacuation control.

Medical Engineering: Infusion pumps with dosage monitoring to prevent overdosing; ventilators with pressure drop alarms; MRI systems with magnetic field protection; pacemakers with battery monitoring.

Railway: Train control systems (e.g., ETCS) to prevent overshooting; signal monitoring with automatic braking; sliding door controls in trains with collision protection; axle load sensors for overload warning.

Aerospace: Redundant flight control systems (fly-by-wire); engine monitoring systems; autoland systems for foggy conditions; drone safety modes with automatic return.

Power supply: Protection relays in substations to prevent short circuits; wind turbines equipped with rotor protection for high winds; transformer monitoring to prevent overload.

Automotive: Automatic Emergency Braking (AEB) to prevent collisions; lane-keeping assist systems with steering correction; airbag systems with deployment logic; adaptive cruise control with distance regulation; battery management systems in electric vehicles to prevent overheating.

What can you expect from us?

Novotechnik supports you in implementing functional safety for your applications by selecting the appropriate products. We work with you to define the functional interfaces between your application and our sensor, and to define and evaluate the safety requirements. Based on this, we provide you with the sensor’s safety parameters, such as MTTFd, DC, and the basis for CCF evaluation.

What we offer:

• The development and production of our standard products are carried out in accordance with the fundamental and proven safety principles of DIN EN ISO 13849
• Our standard products require that safety-related sensor data be evaluated (e.g., through plausibility checks using cross-comparison) by a higher-level system (customer application)
• Our displacement and angle sensors are not safety components as defined by the Machinery Directive 2006/42/EC. Our single- or dual-channel sensors can achieve Performance Level d in Category 3.
• Novotechnik provides safety specifications for the sensor, such as MTTFd, DC, and the basis for CCF assessment, as well as customized FMEDAs for your own safety assessment
• In addition, we develop custom products in the field of position and angle measurement to meet your specific standards and safety requirements

What do you need to do?

You define the safety standard for your entire system and perform a risk assessment. This allows you to determine the required safety level and the specific safety requirements for the components—in our case, the position or angle sensor.

If you have any questions, please contact our experts:

Phone: +49 711 4489-250, Email: support@novotechnik.de