The Murrelektronik MIRO SAFE+ SWITCH H is a 3 NO safety relay that stands as a cornerstone of functional safety technology in industrial automation. Part of the proven MIRO SAFE+ family, this module is engineered to reliably monitor a wide range of safety devices—including emergency stop buttons, safety door interlocks, light curtains, and magnetic safety switches—and to safely interrupt the power supply to hazardous machine movements when a safety condition is violated. The device achieves the highest safety integrity levels, certified to Performance Level e (PL e) according to EN ISO 13849-1 Category 4 and Safety Integrity Level 3 (SIL 3) according to IEC 61508, with a diagnostic coverage (DCavg) of 99% and a service life of 20 years.

At its core, the MIRO SAFE+ SWITCH H provides three positively driven normally open (NO) safety contacts and one normally closed (NC) auxiliary contact for status signaling. The contacts are rated for a switching voltage of up to 250 V AC/DC and a switching current of up to 8 A, with specific ratings of 6 A at 230 V AC for AC-15 applications and 6 A at 24 V DC for DC-13 applications. The safety contacts are designed with forced guidance (EN 50205 Type B), ensuring that a welded NO contact physically prevents the corresponding NC contact from closing, thereby guaranteeing deterministic and safe behavior. The contact material is silver tin oxide (AgSnO), which is self-cleaning and provides excellent electrical life and resistance to welding.

The MIRO SAFE+ SWITCH H is designed for both performance and ease of use. It supports automatic, manual, and manually monitored reset configurations, allowing system designers to select the appropriate restart behavior for their application. An integrated cross-circuit detection function continuously monitors for wiring faults between sensor channels, enhancing diagnostic coverage and preventing unsafe conditions. The module is available in a standard 24 V AC/DC version, as well as a wide-voltage variant that accepts 48-230 V AC for global applications. All versions feature plug-in spring-clamp terminals with unique encoding elements that prevent wiring errors. Clear LED status indicators on the front panel provide immediate visual feedback on supply voltage and safety circuit states, while a designated label area simplifies panel identification.

Installation is streamlined by the module's compact 22.5 mm wide DIN rail housing, which snaps onto standard EN 60715 mounting rails. The device measures 100 mm in height and 121 mm in depth, making it suitable for space-constrained control cabinets. It carries an IP20 protection rating and operates reliably across an ambient temperature range of -25°C to 60°C. With a mechanical life of 10 million switching cycles and compliance with international standards, the Murrelektronik MIRO SAFE+ SWITCH H is an ideal choice for machine builders and system integrators seeking a reliable, certified, and versatile safety relay for safeguarding personnel and equipment in packaging machinery, material handling systems, machine tools, and general factory automation.

Technical Specifications