Bernstein Safety Switch 3911742390

Product Description

This switch features a robust metal housing with a thermosetting plastic cover, providing high mechanical strength and resistance to environmental conditions. It is equipped with two normally closed (NC) contacts, ensuring a safe state when the guard is open or misaligned. The switch is actuated by a separate actuator (sold separately), which is inserted into the switch's head to change the contact state. The M20 cable gland allows for secure and reliable wiring, and the IP67 protection rating makes it suitable for harsh environments where dust and water ingress are a concern. The 3911742390 is part of Bernstein's SLK series, which is known for its modular design and high switching reliability. The switch has a positive break operation, meaning that the NC contacts are forced open when the actuator is removed, ensuring a fail-safe function. This is critical for safety circuits in accordance with ISO 14119 and other relevant safety standards. The switch is designed for use in safety circuits up to PL e (ISO 13849-1) and SIL 3 (IEC 61508), making it suitable for applications requiring high safety integrity. This safety switch is widely used in industrial automation for guarding machine tools, packaging equipment, and other machinery where access to hazardous areas must be monitored. Its compact design and multiple actuation head options (available in different versions) allow for flexible installation. The switch is rated for a mechanical life of over 1 million operations, ensuring long-term reliability. With a rated insulation voltage of 500V and a conventional thermal current of 10A, it can handle typical control circuit loads. The operating temperature range of -30°C to +80°C makes it suitable for a variety of industrial environments. The Bernstein 3911742390 is a safety switch from the SLK series, designed for position monitoring and safety interlocking in industrial machinery.

Basic Product Information

• Robust metal housing with thermosetting plastic cover
• IP67 protection rating for harsh environments
• M20 cable gland for secure wiring
• 2 normally closed (NC) contacts
• Suitable for safety circuits up to PL e / SIL 3
• Positive break operation for fail-safe NC contacts

Technical Specifications

Version & Model Difference

The Bernstein SLK series includes various models with different contact configurations (e.g., 1NC/1NO, 2NC/1NO), actuator types (roller, rod, etc.), and cable entry sizes (M16, M20, or pre-wired). The 3911742390 specifically has 2NC contacts and an M20 cable entry. Other versions may have different head orientations or additional features like LED indication. The 3911742390 is a standard version without LED, suitable for most safety applications.

Application Scenarios