System structure and configuration

As a supplier of a full range of automation products, Nanda Automation Technology Co., Ltd. can provide a complete solution for the tunnel monitoring system.

Solution 1: NA400 PLC

PLC and communication network are the core components of the tunnel monitoring system. The choice of PLC and the performance of the communication network of the monitoring system play a decisive role in the performance of the tunnel monitoring system. Selecting the appropriate PLC and communication network according to the characteristics of the tunnel itself and monitoring requirements is an important factor to ensure the performance of the tunnel monitoring system.

In terms of communications, Nanda Automation provides a wealth of options for users. Whether it is a PROFIBUS communication network constructed based on field bus technology or an industrial Ethernet communication network constructed based on Ethernet technology, it can well meet the requirements of the tunnel monitoring system for the performance and reliability of the communication network.

NA400 series PLC solution, its stable performance, strong communication ability and moderate price can provide users with cost-effective solutions.

The following introduces the industrial Ethernet solution based on Ethernet technology: 

Industrial Ethernet redundant ring network is a powerful area and unit network based on IEEE802.3 (Ethernet). Its technology is fully compatible with ordinary Ethernet, taking into account the harsh working environment and extremely high reliability requirements on the industrial site, Industrial Ethernet has made corresponding improvements to ordinary Ethernet to meet the needs of industrial applications.

Technical characteristics >>>

• Industrial Ethernet technology is compatible with IEEE802.3/IEEE802.3u and uses ISO and TCP/IP communication protocols.
• Redundant 24V DC power supply.
• Simple cabinet rail installation.
• Convenient formation of star, line and ring topologies.
• High-speed redundant safety network, the maximum network reconstruction time is 0.3 seconds.
• Network components can be used in harsh field environments and pass EMC tests.
• Powerful network diagnosis and management functions, support SNMP.
• Support Web-based network management.

As shown in the figure, the communication network of the monitoring system selects an industrial Ethernet redundant fiber ring network. The redundant ring network uses industrial-specific redundant ring network switches to ensure the reliability of network communication. That is, when any point on the network fails, the normal communication of the network can be restored within 0.3 seconds, without affecting the time exchange between the devices. The local controller chooses the NA400 series PLC to realize the input, output and control of on-site digital, analog and serial communication equipment (such as large-scale information signage). The NA400 PLC is connected to the fiber switch on the fiber ring network via Ethernet. The local controller of the main monitoring room selects the NA400 hot standby redundant PLC, which is also connected to the industrial Ethernet redundant fiber ring network through the switch, and uses a touch screen for on-site control and monitoring in the monitoring room. NA400 PLC is responsible for the control and coordination of the entire tunnel monitoring system, and uploads the information of the monitoring system to the monitoring sub-center for the operators to realize centralized monitoring.

Solution 2: NA400 PLC+NA300 PLC

NA400 series hot standby redundant core controller + NA300 series regional controller solution.

Topology diagram of PLC network structure:

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Solution 3: NA400 PLC+NA2000 PLC

 

The monitoring system consists of three layers of network structure: centralized control center, tunnel monitoring center and on-site monitoring terminal. Nanda Auto'mation products mainly complete the data collection of the tunnel monitoring center and on-site monitoring terminal. Among them, the tunnel monitoring center is completed by NA400 medium and large PLC, and the hot standby redundant system solution is adopted, which can realize power supply redundancy, CPU redundancy, and network redundancy to ensure the safety and reliability of data collection. The on-site monitoring terminal mainly adopts the NA2000 series intelligent controller. Based on the development ideas of integration, miniaturization and networking, it is oriented to the core applications of the Internet of Things terminal control unit and the automation terminal mechanical equipment control unit. NA2000 integrates Ethernet interface, multiple RS485 interfaces and rich I/O interfaces, supports bus-type Ethernet cascading mode, and completes data exchange through optical fiber ring network and NA400 PLC.

 

 

 

 

Topology diagram of PLC network structure:

 

 

 

 

 

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Solution 4: NA300 PLC+NA2000 PLC

Topology diagram of PLC network structure:

 

 

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Traffic monitoring system functions 

 

System automatic event monitoring

Stopped vehicle detection, traffic congestion detection, pedestrian detection, vehicle retrograde detection, low speed vehicle detection, abandoned object detection, vehicle detection with distance less than the limit, fire detection, distress detection, and the system can classify the priority of the alarm to avoid Multiple alarms for the same event.

 

Automatic recording

When an accident or traffic event occurs, the system automatically alarms, and at the same time, the automatic recording of the event is not less than three minutes (1 minute before the incident and 2 minutes after the incident video recording and the recording time can be arbitrarily set according to the requirements of the event ). The system transmits and stores these recordings to the central event detection workstation for easy analysis, and provides several recording options: automatic recording when an event occurs, permanent recording, administrator recording, multi-camera recording mode, external trigger recording;

 

All-weather detection function

Regardless of day, night, rain, snow, fog, as long as the human eye can see the movement of the vehicle under various climate conditions, even if the road is not illuminated, as long as the vehicle has normal headlights and taillights, barrier-free detection of various traffic incidents and accidents;

 

Traffic data detection

Traffic flow, average speed, occupancy rate, vehicle spacing, queue length, vehicle type, driving time, vehicle classification (3 types).

The system runs a self-diagnostic program on the analyzer and automatically detects the following errors:

camera position movement, camera signal loss, analyzer error, network communication failure, and system resource status.

 

Incident detection

The computer is responsible for the management, statistics, etc. of the event detection along the line, and transmits the alarm signal to the entire monitoring system.

The system should have the functions of visualization, convenient setting, maintenance and management.

It should have different settings for the operation authority of multi-level users in the maintenance and management area, and support multiple users with different authorities to operate and manage the system at the same time.

 

Data output interface

Standard Ethernet interface, event and accident alarm data can be opened to other application systems through TCP/IP protocol, and can support other uses such as alarm linkage, such as direct control of the video matrix switcher, integrated alarm management platform, etc.