Visualization and control of the streetcar maintenance facility in the Brno district of Pisarky

In the spring of 2020, the Brno Public Transport Authority's new streetcar maintenance facility was put into operation in the district of Pisarky. This state-of-the-art workplace increases the quality and efficiency of daily cleaning works and technical condition inspections for up to 130 streetcars.

In addition to its technical function, the facility also plays an important role in terms of architecture.

The streetcar maintenance facility in the Brno district of Pisarky

Naturally, the new building comes with new technical systems. For control and visualization purposes, a system consisting of the Reliance SCADA system and Teco, Siemens, and ifm PLCs was installed at the streetcar maintenance facility.

Control system

The control system is designed to monitor the passage of streetcars through the facility from registration to parking in a designated parking place.

Among other things, the system allows the operator to:

• Monitor positions of vehicles
• Set track modes
• Manually take control of track sections
• Set parking modes
• Set gate modes
• Locate and take over vehicles
• Control switch heating

The system ensures the smooth passage of vehicles using traffic signals for drivers. It constantly monitors the length of the vehicle and compares it with free space on the tracks. According to available data (a streetcar's length, line, number, modes, etc.), the system decides on the vehicle's route so that the passage is smooth and so that the vehicle doesn't block the road, which would make it impossible for other streetcars to enter the maintenance facility. Blocking the road could also stop traffic flow at intersections or cause gate malfunctions (especially in the winter months).

Upon its arrival at the facility, each vehicle's undercarriage and electrical equipment are inspected. Also, its interior is cleaned and disinfected. The technician decides on the condition of the vehicle and whether maintenance works are needed. After that, the streetcar is parked and assigned a line, a route for the following day including the exact time of departure, and a parking track. The streetcar then exits the facility and, with the help of traffic signals, is directed to the parking track. This track and its position are displayed on a large screen at the drivers' stand, which allows them – before starting their shift – to find the parking position of their vehicle within the maintenance facility.

The solution is decentralized. Its individual parts control the connected switches regardless of the system status, which is used mainly in the event of a failure or during service works. When in normal operation, the system works as a whole and its software component (Reliance SCADA) gathers and integrates data from the PLCs.

A picture of the main control room

The control system's other functions are:

• Communication with a vehicle through the RS485 interface
• Communication with the passenger information system via UDP datagrams
• Measuring the occupancy of the undercarriage maintenance area
• Acquiring the streetcar's number, length, and wash flag
• Reading parking places from the public transport authority's database
• Controlling railroad signals by inspection staff
• Detecting track occupancy through the RS485 interface
• Controlling monitors using TCP/IP communication

Examples of visualization windows