Encoders Used for Position Measurement in Industrial Automation

Encoders used for position measurement in industrial automation play a vital role not only in production efficiency but also in occupational safety. Especially in systems with human-machine interaction and hazardous movements, standard encoders are no longer sufficient.

In this article, we detail the main technical differences between standard (classic) encoders and safety encoders, and explain with examples where and why you should use safety encoders.

What is a Standard Encoder?

Standard encoders are sensors that measure the position, speed or direction of machine parts and convert this information into digital (or analog) signals. These encoders:

• Generally operate in single-channel mode
• Provide standard signal outputs (NPN, PNP, TTL, HTL, SSI, etc.)
• Provide position data, but do not guarantee that this data is safe
• Do not have safety classifications such as SIL / PL

These types of encoders are preferred in non-hazardous systems and low-risk applications.

What is a Safety Encoder?

Safety encoders go beyond the functions of standard encoders by offering:

• Safe position and speed monitoring
• Fault detection and error reporting
• Redundant sensing
• Communication with safety protocols (e.g., PROFIsafe, FSoE)
  and are SIL2/3 or PL d/e certified.

All these features make safety encoders an active component of machine safety systems.

Tabular Comparison of Technical Differences

Technical Criteria	Standard Encoder	Safety Encoder
Safety Certification	None	SIL2 / SIL3, PL d / PL e
Signal Output	Single output, no fault control	Dual channel (redundant), fault control
Fault Detection	None	Cable break, signal mismatch detection
Protocol Support	SSI, Profibus, Profinet etc.	PROFIsafe, CANopen Safety, FSoE
Diagnostics	None	Internal self-check / watchdog systems
Behavior After Power Loss	Data may be lost	Continues with fail-safe operation
Compliance with Safety Functions	Not compatible	Fully compliant with EN ISO 13849 and IEC 61508
Application Area	Basic position monitoring	Hazardous machines, AGVs, robotic arms
Price	More affordable	Higher – due to safety requirements

In Which Applications is a Safety Encoder Mandatory?

According to CE directives and EN ISO 13849/IEC 62061, the use of safety encoders is mandatory or strongly recommended in the following systems:

• Eccentric and hydraulic presses
• Elevator and crane systems
• Industrial robots and cobot systems
• Automated storage (AS/RS) and AGV systems
• High-speed production lines
• Food or pharmaceutical filling lines (may require IP69K + SIL)

TR Electronic Safety Encoder Technology

As the distributor of TR Electronic, a Germany-based manufacturer, we offer SIL2/SIL3 and PL e certified, high-precision safety encoders that are leading the global market.

The TR Electronic safety encoder product range includes:

• Magnetic or optical sensing technology
• IP65/IP67/IP69K protection
• PROFIsafe, FSoE, CANopen Safety support
• Special solutions for food, automotive, textile, and packaging industries

While standard encoders deliver successful results in standard applications, in machines where human safety is at stake they are no longer sufficient. Safety-certified encoders become not only a measuring device but also a safety component of the system.

To meet legal requirements, build CE-compliant systems, and ensure human-machine safety, choosing a safety encoder is essential.

📞 Technical Support and Product Consultation

For your safety encoder projects, contact our expert technical team:

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