Abstract
The article proposes the synthesis features of a modelling algorithm. This algorithm is used to probabilistic reliability estimation and safety of railway automation and remote-control devices. It is used at the stages of development and operational safety proof. To solve the problem, it is proposed to use the simulation method. A direct process simulation model that reproduces the following processes: failure processes, failure detection processes in a system component, system recovery processes. The article describes the following refined definitions: obscure failure, protective failure, dangerous failure, states for the main redundant structures of railway automation microprocessor systems. In the article a formulates the principles and requirements for software tools for building a simulation model. It is proposed to use the GPSS World system as a software tool. Considering the peculiarities of GPSS World and on the formulated principles basis, a modelling algorithm has been designed. The obtained algorithm provides the simplicity of the GPSS-model implementation, which makes it possible to estimate the rates of obscure, protective, and dangerous failures in redundant structures. And similar structures are used to develop the railway automation systems.