The RMM (Remote Monitoring Modem) is the key component in power-line communication for monitoring and control of reefer containers.  

Each container equipped with an RMM is able to send data on its operating conditions and alarms to a central monitoring system, such as the REFCON system.  

Besides monitoring, the RMM can be used to remotely control various reefer container functions, which include changing the setpoint, initiating defrost, and activating automatic pre-trip inspection.