NR BR 1904A ISSUE C PDF

GENERAL

Data link modules (DLMs) part of the serial data distribution system between the solid state interlocking and the trackside functional module (TFM) which it controls. The modules perform the two main functions of transmitting data from the solid state interlocking to the TFM and then returning data from the TFM to the solid state interlocking.

The module shall be capable of connection to up to six trackside functional modules at the lineside or four multiprocessor modules at the interlocking. The module shall also be capable of driving two electrically isolated data link systems.

The module may also be configured as a repeater in order to extend the transmission line by working two modules "back to back". In this mode the module may be connected to a maximum of five TFMs. The detailed operation and connection configuration are contained in the SS1 Code of Practice SS1 8500.

This specification states the Engineering requirements for a solid state interlocking module for data transmission.

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