PT 62912-2 - TC 9/PT 62912-2

IEC 62912-2:2019 gives requirements for direct current relays intended for safety-related applications in railway signalling installations.
This document is applicable to non-proved signalling monostable relays of the spring type, whose return force is generated by elasticity of spring.
The return force can be provided either from a separate spring and/or from the contact springs themselves.