TPC 300 is a multi-functional controller for controlling and monitoring thermoelectric coolers and dehumidifiers. In addition to various control programs, there are extensive monitoring options and a serial interface for communication. Temperature and humidity in the control cabinet are regulated.The function of the fans, the Peltier elements, and the internal temperature are monitored. Two more temperature sensors can be placed, for example, on one of the heat sinks and also used for monitoring.