Safety Control Unit SR3D – Maximum Safety and Reliability for Industrial Applications

The SR3D is a universally applicable safety control unit designed for the safe monitoring and control of machines and systems. With its three safe relay outputs, it enables quick and secure shutdown of moving parts of a machine in the event of a hazard.

Applications of the SR3D
The SR3D is ideally suited for:

• Emergency stop circuits (single or dual channel)
• Safety guard monitoring
• Applications in combustion plants (according to EN 50156-1 and EN 746-2)
• Use in maritime environments (certification by Germanischer Lloyd)

Functional Features of the SR3D

• 2 possible start behaviors:
- Monitored manual start
- Automatic start

• Cross-fault and ground-fault monitoring to ensure signal integrity
• Maximum safety category: Up to PL e, SILCL 3, Category 4
• Redundant design: Three safe, diverse relay outputs and one auxiliary contact (monitoring contact)
• Connection options:
- Emergency stop buttons
- Safety switches
- Contactless safety switches
- Safety components with OSSD outputs

Safety Concept
The SR3D ensures reliable and safe separation of safety circuits in accordance with EN 60204-1. With its cyclical self-monitoring, the device automatically detects contact faults, such as contact welding or line breaks, and signals them in good time.

Safety Functions of the SR3D

• Feedback loop: Monitors downstream contactors or expansion modules.
• Cyclic monitoring of the output contacts to detect errors at an early stage.
• Status display: The switching status is visualized by LED indicators, which facilitates maintenance and diagnosis.
• Redundancy with force-guided relays: Even in the event of a single fault within the device, the safety function is maintained.

Technical Specifications

• Protection class: IP54 (must be installed in control cabinets)
• Mounting: On 35 mm DIN rail according to EN 60715 TH35
• Operating voltage: AC 115 V / 230 V – A minimum distance of 10 mm to adjacent devices must be maintained
• Accessories: Spacers from ZANDER AACHEN (Art.-No. 472596) for defined distance control

Certifications and Standards
The SR3D meets the highest safety standards and is certified according to:

• EN ISO 13849-1 (PL e)
• IEC 61508 (SIL 3)
• EN 60204-1
• Certification by TÜV Rheinland and Germanischer Lloyd

Installation and Setup

• Mounting on a 35 mm DIN rail according to EN 60715 TH35.
• Ensure adequate heat dissipation in the control cabinet.
• Maintain a distance of at least 10 mm for the AC 115 V / 230 V version.

Conclusion
The SR3D safety control unit offers comprehensive safety, reliability, and easy maintenance. Thanks to its high safety standards and certifications according to SIL 3 and PL e, it is indispensable in industrial applications. The redundant design with force-guided relays and the self-monitoring function make it one of the safest and most reliable safety control units on the market.
With the SR3D, you are always on the safe side – whether in machine monitoring, combustion systems, or maritime applications.