Definitions of Commonly Used Terms in the World of Safety Relays Advantages of mechanical contact systems: Force Guidance of contacts provides designers of safety relevant circuits with all the fundamental details upon which they can build up their circuit technology

IEC/EN 50205 Section 3.1: Switching Relays with Force Guided Contacts: Switching relays with at least one NC (Normally Closed) contact and one NO (Normally Open) contact, exhibit a mechanical design preventing simultaneous closing of the NO and NC contact at