The SmartMaxII is a microprocessor-controlled standalone monitor designed for all indoor & outdoor field installations. The SmartMaxII generates three types of output signals: relay contacts from 3 relays, an analog 4-20mA output signal, and a digital serial link (RS-485 Modbus half duplex) which permits bi-directional digital communications. Multiple monitors can be arranged in any order on a single 3-wire communication line, thereby reducing wiring requirements.