Dissolved Oxygen Transmitter ATI Q45D is an industrial online dissolved oxygen analyzer for continuous water and process monitoring. It supports optical and galvanic sensors and delivers accurate real-time measurement through a standard 4–20 mA output. With a clear LCD display, easy calibration, flexible power options, and a rugged NEMA 4X / IP66 enclosure, this dissolved oxygen sensor transmitter is ideal for wastewater, water treatment, and industrial water quality applications. Applications: Aeration systems, fish farming, wastewater effluent monitoring, water distribution systems, rivers, streams, and related water bodies.