Summary
Highlights
The SICAM FRTU 6MD25 is presented as an intelligent electronic device for smart grids. The necessity for smart grids is highlighted due to the growing electricity demand and complex power networks with bi-directional flow, requiring automation, supervision, monitoring, and control. The FRTU interfaces with Ring Main Units (RMU) to manage power distribution.
The FRTU communicates fault status to the distribution management system. An example is given for a fault on feeder R1, where relevant switches are opened or closed by FRTUs to isolate the fault. This ensures quick restoration of service with minimal impact on consumers.
The FRTU features a modular and scalable architecture with a power supply, central processing unit (CPU), and input/output (I/O) cards. I/O cards are interchangeable and can be easily inserted or removed. Detachable, self-locking connector terminals and various LEDs for monitoring power, status, and diagnostics are also detailed.
The power supply has two variants and can be switched on/off via a front switch with a pull-and-push security mechanism. The CPU handles acquisition, conditioning, and output of information, and communicates with power meters using Modbus protocol over RS-485 ports, indicated by TX/RX LEDs. A Volt LED shows the health of communication links between I/O cards and the CPU.
Available communication interfaces include USB, RS-232, RS-485, and Ethernet. The analog input card offers eight user-configurable inputs (unipolar or bipolar voltage and current). The digital input card has 16 configurable digital inputs, storing up to 200 status change events, with individual status LEDs. The digital output card provides eight outputs to control power system devices like circuit breakers, also with individual status LEDs. The module can be expanded to include up to eight I/O cards.