CARLO GAVAZZI launches the DMPU Series Motor Protection System. The DMPU is a modular electronic motor protection relay to control, monitor and protect the performance of 3-phase constant or dual speed, AC induction motors.  The DMPU device measures electrical motor variables (voltage, current, harmonic distortion, power, energy and earth leakage current), monitoring overloads through the thermal model, controlling them and measuring other variables, such as motor and bearing temperature. Finally it includes a data logger function for storing trends of the electrical variables, alarms and fast data logging for storing start-up profiles.

Through the communication features, it is possible to transmit all monitored variables to a supervision control system for data collection and process control. Profibus and Modbus TCP/IP protocols are available to easily insert the DMPU Series into a majority of applications. The HMI operator interface is freely programmable and can show instantaneous values and alarm messages. Windows based DMPU-PS configuration and monitoring software, simplifies plant design through graphic block configuration and connection, where the blocks are all the variables that can be used, as inputs, outputs, ANSI function, electrical and temperature variables, logical functions, timers and counters.

The DMPU Series allows protection of the motor against damage due to thermal effect taking place during overload condition. The protection trips when motor temperature exceeds calculated TCU parameter as well as optional temperature measurements and electrical variables. The DMPU implements several ANSI functions to protect motor from operation that may damage it. For example ANSI 46 (motor inverse current), ANSI 51 LR and ANSI 48 (locked or stalled rotor) and ANSI 46 (earth leakage) are among few that are supported. All control functions such as start, stop, reverse, star-delta control and alarm indication are possible with push buttons, touch screen HMIs or communications.