The thesis is based on the renewal and modernization of control system for lifting locomotives in the company SZ – VIT. The need for renewed control system has been seen during uncontrolled operation, which highlighted certain shortcomings in the system of reliability, in particular, the safety of people and the locomotives. At lifting or lowering locomotive, one of the motors didn't work properly, which caused asymmetric vertical movement of the locomotive and without operator's intervention, it could lead to accidents with major material damage. Analysis of the incident revealed several weaknesses of the existing control system.
Without automation and control of the drives, reliable and secure operation were highly dependent on the operator's attention.
The thesis shows the process of implementation of the existing automation system for lifting locomotives, from project planning for execution, manufacturing control cabinets with wiring of power and control elements, software development, testing signals, the start-up and design of the project works carried out .
Such automation requires a programmable logic controller (PLC), which carries out logical operations. To determine the position of the individual jacks, we used inductive sensors and limit switches, which are connected to the PLC. For the safty of the system we used safety relay, which controlls emergency stop buttons and bimetal circuit breakers for motors.
With the renovation we have achived a higher level of security and increased reliabilty of the system. We have also extended the life time of machine elements. Because of limited financial resources, we used many of old existing working elements, which were getting a bit over the years, but still performing their function. At the different financial situation in the future, the system can be upgraded.
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