Moxa's PoE Application Used for Cargo Container Security
Introduction Cargo container security involves creating a system that secures and tracks shipping containers. The system can detect theft, smuggling, international terrorism, and track freight containers to streamline the supply chain as it moves through the port infrastructure and intermodal rail and road connectors.
System Description The surveillance system requires PoE switches that can power each cargo container and then transmit data back to the control room for analysis and monitoring.
To be able to connect the control room to the sensors installed in the cargo containers, the PoE switches used for this application needed to have at least 6 ports: 2 Ethernet ports for connecting to the control room and other PoE switches, and 4 ports to power card readers used to monitor access to the containers.
PoE switches not only transmit data to and from Ethernet devices, but they also deliver power to devices, giving administrators more versatility for placing devices in out of the way places. In fact, using PoE switches for this application resulted in great reduction in the cost of installing power cables in hundreds of cargo containers.
The switches are installed in weather protected metal cabinets that can experience significant temperature changes as the sun rises and sets, and as the container is transported from one place to another. Temperatures inside the cabinet could reach as high as 70°C, or as low as -30°C. To ensure that the switches operated reliably in extreme temperature conditions, the application called for switches that support an extended operating temperature range of -40 to 75°C.
Network System Diagram
Moxa's EDS-P308 has 8 ports (4 ports for PoE, 4 ports for Ethernet), making it suitable for a variety of applications.
Two models of EDS-P308 are available:
• Standard operating temperature model for 0 to 60°C environments
• Extended operating temperature model for -40 to 75°C environments
The EDS-P308 series has two power inputs that can be connected simultaneously to live DC power sources. If one of the power inputs fails, the other live source acts as a backup to provide the Ethernet switch's power needs automatically.
The EDS-P308 series has relay contact outputs to send warning signals to technicians on the shop floor when the power fails or a port link breaks, allowing the technicians to respond quickly with appropriate emergency operation procedures.