NR SSI8003-40B ISSUE 2 PDF

Introduction

SSI Simulator

A Simulator MPM is used in a SSI Design Workstation simulation system or to replace one of the three Interlocking MPMs in a SSI Central Interlocking during testing, to simulate incoming telegrams from Trackside Functional Modules and other Central Interlockings. The telegrams to be simulated are specified in the Simulator MPM's geographic data, which is generated by a compiler which forms part of the SSI Design Workstation data preparation facilities. The Simulator MPM is usually used in conjunction with a Technician's Terminal or Interface Processor which provides an interface to a colour graphic display and trackerball which are used to generate instructions to the Simulator MPM to amend the content of the telegrams being simulated to represent events at the trackside or in adjacent Interlocking areas.

Optionally, the Simulator MPM geographic data may also include information to allow train movements to be simulated by sequences of telegram changes which represent track circuits being occupied and cleared. The simulated trains move in response to the state of the bits in the output telegrams from the Interlocking MPMs which control signal aspects and points controls. Facilities are provided for trains to be created and deleted from the simulation at selected locations, allowing simulation of train movements across Interlocking boundaries.

The purpose of this document is to describe the content of the Simulator MPM data. This document should be read in conjunction with the "SSI Design Workstation Users' Guide", which deals with the mechanics of entering data into the workstation databases and source text files, running compilers, testing data and programming PROMs. It is also assumed that the reader is familiar with the documents for Diagnostic and Interlocking data preparation (SSI8003-30 and SSI8003-10 respectively).

The geographic data for the Simulator MPM is generated from two sources:

(i) The scheme design database which specifies the name and identity number of each Central Interlocking, the equipment connected to each Trackside Functional Module, and the information contained in the Internal Data Link telegrams used to communicate between Central Interlockings within the Control Centre.

(ii) A source text file (referred to as the SIM file) which specifies the paths which may be taken by trains through the controlled area, with references to signal, point and track circuit names. The length of each track circuit and the speed limits which apply are specified, together with any other features which may affect the movement of simulated trains. This file need only be created when train simulation is required.

Sections 2 & 3 of this document describe how the Simulator MPM data compiler derives its information from the scheme design database to simulate telegrams on the Trackside and Internal Data Links, Chapter C Section 1 describes the principles behind train movement simulation, and Chapter C Section 2 describes the train simulation data in the SIM file in detail.