Safety interlock switch is tamper-resistant

Paul Boughton

Ensuring long-term reliability in hostile environments is not the only challenge facing machine safety systems: providing a high degree of resistance to tampering helps to prevent the unauthorised overriding of safety interlocks and is also an important aspect of maintaining system integrity.

The latest safety interlock switch from Scientific Technologies Inc (STI) is designed with both security and longevity in mind.

The new MFS standalone safety interlock switch requires both magnetic and ferro-resonant signals to close the safety signals, making it highly resistant to tampering and yet reliable in operation. In lower-risk applications it can be used as a standalone safety switch, and is capable of direct switching relays and contactors up to 2A at 230 V AC. For applications that require a higher degree of safety integrity, the MFS can be coupled with safety-monitoring relays for added security. A visible indication of the switch's status is provided by a built-in LED indicator.

A Nema 6 (IP 67) rated housing makes the MFS water resistant and suitable for use in water wash-down environments. STI has designed the MFS for exceptional longevity - in excess of 10 million operations - making it highly suitable for machine guards and guard doors where significant repetition of operation is required. MFS switches come pre-wired and are designed to mount quickly and easily on standard-sized trunking. Combining security, resilience and a long lifespan, MFS switches suit a wide variety of machine guarding applications.

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