Additional Information

Technical Article

Relays with forced guided contacts are used in safety orientated applications for the decoupling of different voltage potentials wherever humans need to be protected from injury and expensive equipment needs to be protected from damage.   These relays permit the implementation of self monitoring systems and are used in applications ranging from emergency off circuits to elevator controls to complex machine controls.  They are often a fundamental part of achieving conformance with safety standard AS61508 – Functional safety of electrical electronic programmable electronic safety-related systems.

Compliant to European standard EN50205, our safety relays (manufactured by Elesta Relays in Switzerland) consist of a minimum of one normally open and one normally closed contact.  Make and break contacts must never be closed at the same time for the whole life of the relay.  The contact spring assemblies and other conducting parts in the relay are designed to ensure no short circuits of conducting connections can occur. Additionally the insulation values are subject to higher standards and pollution degree-2 is defined for forcibly guided contacts. B10 and B10d life figures are also defined, allowing the Safety Integrity Level / SIL of the application safety circuit to be defined according to AS61508. A white-paper titled “What is AS61508 and how is it different from AS4024?” is available on request, which includes the importance of following AS61508 from the outset.