The JUMO dTRON 3xx plast controller series consists of three freely programmable devices in various DIN formats to control temperatures and other process variables for special applications in the plastics industry. Fields of applications include, for instance, extruders, injection molding machines, temperature control units, and hot channel systems. The high-contrast multicolor LCD display for actual value, setpoint value, and operator guidance consists of two four-digit seven-segment displays, two single-digit 16-segment displays, display of active setpoint values, six relay status indications, and display of unit, ramp function, and manual mode. Simple operation with four keys. The devices can be used as 2-state, 3-state, three-step controllers, or continuous controllers. The controller software contains, among others, a hot channel warm-up ramp function, control circuit and output value monitoring, two self-optimization methods, a math and logic module as well as four limit value monitoring functions. The linearizations of the common measuring probes are stored; programming of a customer-specific linearization table is possible. A setup program is available for user-friendly configuration from a PC. The devices can be integrated in a data network using a RS422/485, PROFIBUS-DP, or a current interface. The electrical connection occurs at the back with screw terminals. The above block diagram displays the possible input and output configurations. The option boards are universally applicable for all devices in the series.