REFCON is an integral reefer container monitoring system, which uses the reefer container’s own power cable to transmit data between the container and the computer monitoring system on the vessel or in a container terminal.

REFCON fully complies with the ISO 10368 Standard for reefer container monitoring using Power Cable Transmission.  

Link to ISO 10368 standard  

Modern reefer containers are controlled by a micro-processor which, sends and receives information via a modem installed inside the container. The modem uses the power line to communicate with the Master modem installed on the vessel or terminal. The Master modem passes data between the power line and the computer monitoring system using RS 485 protocol.  

 Please see the diagram.