The Importance of IP Protection Class in Encoder Selection for Industrial Environments

Modern production lines and industrial machines must meet high standards not only in terms of efficiency but also in terms of safety. At this point, accurate detection of the control, state, and position of moving machine parts becomes critical for human safety and process integrity.

Exactly here, safety-certified encoders become an integral part of machine safety systems. In this article, we detail the encoder’s role in safety systems within the framework of international standards such as CE, SIL, PL, EN ISO 13849.

What Is the Encoder’s Fundamental Role in Safety Systems?

Encoders report the position, speed, and direction of moving parts to the control system, making machine operation observable and controllable. In safety scenarios, this data enables:

Early detection of hazardous motion
Triggering of emergency stop (E-Stop) algorithms
Providing the basis for functions such as Safe Speed, Safe Direction, and Safe Stop

Safety encoders can detect not only position but also defined fault conditions (e.g., cable break, magnetic interference, signal synchronization error).

What Are CE, SIL, PL, and EN ISO 13849?

✅ CE Mark (Conformité Européenne)

Legally mandatory for machines to be sold in the European Economic Area.
The CE mark indicates that the product meets essential safety and environmental requirements.
Compliance with standards such as EN ISO 13849 is required for CE.

✅ SIL (Safety Integrity Level) – IEC 61508 / IEC 62061

A risk reduction level indicating how safely a system operates.
Levels range from SIL1 to SIL4 (SIL4 is the highest).
Safety encoders are typically certified at SIL2 or SIL3.
Common in automotive, packaging, textile, and press machines.

✅ PL (Performance Level) – EN ISO 13849

Primarily used for machinery safety.
Five levels from PL a (lowest) to PL e (highest).
Encoders at PL e level are used for safe position and speed monitoring systems.

✅ EN ISO 13849

One of the most important standards for machine builders.
Evaluates the safety functions of control systems.
Determines the conformity of all components used in functions such as safe braking, guard locking, and speed monitoring.

How Do Safety Encoders Make a Difference?

The safety encoders of our distributed brand TR Electronic are certified to SIL2/SIL3 and PL d/e levels. These encoders:

Ensure signal integrity with a dual-channel output
Provide a redundant architecture for safe reaction in fault conditions
Keep the system under continuous control thanks to built-in diagnostics
Are ready for direct use in EN ISO 13849-compliant applications

Real Application Examples:

In eccentric presses, to prevent the die from moving outside the safe zone
In automatic doors, to prevent human contact using position information
In AGVs and autonomous robots, to enforce safe speed limitation

Key Considerations When Selecting Encoders for Safety Systems

Criteria	What to Look For
Certification	SIL2/SIL3, PL d/e
Output type	Redundant (dual) output
Interface	PROFIsafe, FSoE, CANopen Safety
IP protection rating	IP65–IP69K (depending on environment)
Diagnostics and fault reporting	Integrated on-device fault reporting

Conclusion

Today, machine safety is not optional—it’s mandatory. Safety-certified encoders have become components that not only perform position measurement but also directly affect the safety of people and systems on your production line.

The TR Electronic safety encoder solutions we distribute are developed with high-quality German engineering and meet CE, SIL, and PL requirements.

Get Technical Consulting or Application Support

Benefit from our engineering support for selecting safety encoders suitable for your systems and for system integration:

📧 info@trelectronic.com.tr
📞 +90 232 382 23 15