scope:

This standard applies to vital signalling timers which energise an output after a predetermined time. It does not include the remote electrical controlling circuitry. The introduction of this standard does not mandate the replacement of timers which are in service and have been procured to a different specification.

The timer is not a replacement for ratchet type timers or those for which a suitable appendix does not exist.

PURPOSE

This specification defines the minimum performance requirements for a Vital Signalling Timer procured for use in signalling applications. Common requirements for all timers are given in the main body of the specification and the requirements specific to the different variants are given in the Appendices A to D. The pin registration codes are allocated to the timers in accordance with GK/RT0330.