Visualization and control of the Valik tunnel, the first highway tunnel in Czechia

Tunnel Valik together with a bridge across the Uhlava river belongs to the last section of the by-pass highway of the city of Plzen and D5 highway leading from Prague to Rozvadov.

The control system for the tunnel was implemented by two Czech companies, GEOVAP and Teco. Tecomat PLC devices provide control of the tunnel. The Reliance SCADA/HMI system provides visualization of the tunnel and saves data from the operation.

Tunnel Valik with its 380 meters in length ranks among shorter constructions. But with its traffic density of more than 20,000 vehicles per day, it ranks among the constructions with the highest requirements for the equipment from the safety point of view.

Tunel Valík

The control system has the following structure

• The main control room (consists of several PCs connected to the local network) of the Police and Road and Motorway Directorate of the Czech Republic located in Svojkovice
• The backup control system located in the technical station nearby the tunnel
• The entire control system is divided into three parts: control and visualization of the traffic in the tunnel including overhead signs, control and visualization of the traffic in front of the tunnel, and control cabinet with the Tecomat TC700 PLCs

The control room of the Police and Road and Motorway Directorate of the Czech Republic located in Svojkovice

The main control room in Svojkovice

The main control room, located 25 kilometers away from the tunnel, is equipped with two computer stations. The traffic in the tunnel is displayed on the screen (controller) mounted on the wall in the Police and Road and Motorway Directorate's control room. Reliance SCADA provides control of the traffic in the tunnel including the control of the overhead signs. The tunnel is controlled by seventeen Tecomat TC700 PLCs.

The implementation of the control system included the installation of a data server. This data server, with the Reliance Control Server software, is directly connected to the control computers in the main control room. The data server provides historical data that can be displayed on the screen in the control room, communication with other systems connected to the network, and data logging from the operation.

The large screen in the control room

The main control room is also equipped with

• Two "monitoring" stations without control rights used by technicians – they are placed in the control room in Svojkovice
• An independent station for video supervision provides self-transmission of the video signal from the tunnel; mutual interaction between the video supervision station and video detectors is provided by direct connection between the main switchboard and the control system (in the technical room near the tunnel)
• An independent station of the highway information system that receives data from the highway and tunnel traffic
• An independent station that can automatically detect traffic violations, measure section speed, weigh the trucks driving through the tunnel

An overhead sign displaying important information for the drivers

A picture of the Valik tunnel

Communication

Each PC workstation in the control room is equipped with two network cards for direct connection with the main and backup control systems of the tunnel. The Tecomat system is connected to each superior computer through a common physical network connection.

The Reliance SCADA/HMI system continuously provides communication with data sources and controls their validity. It visually informs of the condition of communication and data validity of each object by means of yellow or red frames. It also monitors which PLC in the tunnel is the primary or the backup one and, in case of their possible substitution, it automatically switches to the primary PLC. The system controller is informed about this substitution.

The tunnel traffic control system

The system controller (screen mounted on the wall) has several view screens at his/her disposal. The traffic scheme is the basic scheme being used.

The top part of the screen includes:

• Stable status information that does not change even during switching to another windows
• Basic information on possible fire occurrence, overview of basic physical values and illumination
• Power supply conditions of the whole tunnel
• Tunnel mode of the operation

The main screen includes:

• Stationing (i.e., distance in kilometres of the D5 motorway measured to Prague)
• Condition of SOS boxes in the right tunnel tube and on portals
• Condition of video monitoring cameras in the right tunnel tube
• Setting of concrete variable traffic signs on the portals before and inside the right tunnel tube
• The same items are for the left tunnel tube
• Condition and remote control of the gates in the fencing before and behind the tunnel
• Left corner – condition of cameras for traffic violation monitoring
• Video detection system messages together with the display of the detected zones and text messages of the incident detected

The bottom bar is used for the monitoring and confirmation of all system messages.

• Different colors are used for faults, warnings, simple messages, etc.
• Monitoring, display, and saving of event location, time of occurrence and disappearance of the event, text description
• Here, alarms and events requiring confirmation are cleared/confirmed by the system controller

The bottom part includes a number of buttons for switching to the following view screens:

• Process – air-conditioning
• Illumination
• Power supply
• Air-conditioning of the operation and technical station
• Service

Examples of visualization windows