NR BR 1908 ISSUE A PDF

GENERAL

This Specification states the specific engineering requirement for a solid state interlocking Panel Processor Module ("PPM").

PPMs are the interface between the triplicated Multiprocessor Modules (the interlocking) and the Panel Multiplexer. They are connected also to the technician's terminal and external systems such as train describer or automatic route setting.

A Solid State Interlocking is provided with two PPMs in order to increase system availability. They are connected together so as to ensure synchronous operation and to detect the presence (or absence) of the other panel processor module. The system must continue uninterrupted when one module fails.

The module shall meet all the requirements of BR Specification 1900 unless otherwise stated.

A "SYSTEM" indication shall be provided on the front of the module and "POWER" and "SYSTEM" indications on the rear of the module.