Nust invents railway signalling system

Brighton Gumbo Business Reporter
THE National University of Science and Technology’s electronic engineering department has invented a Programmable Logic Controller (PLC) based railway signalling system that controls and monitors train movements.

Speaking to Business Chronicle on the sidelines of a three-day inaugural Research and Intellectual Expo at the university yesterday, former National Railways of Zimbabwe (NRZ) signal instructor and a student at the academic institution Obert Lazalo said he was behind the project.

He said the main idea behind the project was to create a rail system with fewer cables and relays.

“This software-based train movement, monitoring and control programme allows the operator to communicate with the drivers of trains in a more safe way to avoid conflicting movements,” he said.

“It’s an interlocking system whereby conflicting movements are discouraged for example, two signals opposing each other can’t be cleared at the same time, so drivers only have to follow colour insignia in their movements .”

Lazalo said the system being locally manufactured; maintenance and fault clearing would be manageable to local technicians.

“Nothing much was changed in terms of the hardware, this was to ensure user friendliness and understanding of the system by the technician because adopting foreign concepts was going to attract costs of hiring foreigners for maintenance and resolving technical services,” he said.

He said designing something using local resources could create jobs for locals and promote local technical industries.

The railway signalling system project was initiated in September last year and was on display at this year’s Zimbabwe International Trade Fair.

Lazalo said apart from monitoring and controlling train movement, the objective of the PLC based railway signalling system was to minimise copper theft by reducing the number of copper cables and rails used.

He said the project was in line with his job at NRZ where he observed some loopholes in the communication used by the parastatal.

“I observed that the system used by NRZ had challenges, for instance in terms of mishaps in the communication between the operator and the drivers and also the amount of copper which was stolen in various areas,” said Lazalo.