APAX-5520 series controllers offer a compact size without fans. These controllers have no rotating parts, helping further increase system reliability. APAX-5520CE with Xscale PXA270 520 MHz features a VGA interface, enabling local displays, and its RS-485 and LAN ports offer communication ability with Modbus protocol. Internal CF slot and battery backup RAM can be used for data storage. These features make APAX-5520CE as compact and robust as a PLC, but with enhanced displays, connectivity, and storage.