Protective relay (Italian DK5600 spec)
Protection device for electrical grids (compliant with the DK5600 specification by ENEL and certified at Eurotest lab) used by customers who want to connect to the ENEL medium voltage network.
The CPU board contains a low-cost 32-bit ColdFire microcontroller by Freescale (IDE: CodeWarrior) which interfaces with various devices (Real-Time Clock and EEPROM via SPI, UART via RS485 serial port, etc.)
The application firmware uses a real-time proprietary kernel and it handles data acquisition (e.g. electrical signals from the network), signal filtering and processing (RMS values are computed by means of the Fourier transform), protection logics, MMI (push-buttons, LCD display and LED's), communication with a PC (Windows application for configuring the device, reading measurements, etc.)