・New Rosemount™ 490A delivers fast, accurate digital DO measurements across liquid & gas applications.
・Modbus-enabled for seamless integration into modern control systems.
・No electrolyte refills needed thanks to EPA-approved optical sensing tech.
・Two-year sensor cap minimizes downtime and cuts long-term maintenance costs.
・IP68-rated compact design with flexible installation for harsh industrial environments.
Smart Optical Sensor Revolutionizes Dissolved Oxygen Monitoring with Faster Start-Up, Broader Compatibility, and Minimal Upkeep
Emerson’s New Digital Dissolved Oxygen Sensor Enhances Operational Versatility with Lower Maintenance Costs
Shakopee, Minn. (April 17, 2025) – Emerson has introduced the Rosemount™ 490A Optical Dissolved Oxygen Sensor, a cutting-edge measurement solution built for operational flexibility, simplified maintenance, and high-performance monitoring in challenging environments.
Unlike traditional dissolved oxygen (DO) sensors that rely on analog signals and frequent calibration, the 490A features advanced optical sensing and digital Modbus RTU communication, enabling fast, accurate, and stable measurements across multiple industries—including water/wastewater treatment, food and beverage, biopharma, and steam power generation.
The 490A provides accurate DO readings in just 90 seconds from dry to wet conditions and can operate in both gas and liquid media without separate calibrations. With a two-year sensor cap lifespan and no need for electrolyte refills, it dramatically reduces maintenance downtime and cost compared to traditional amperometric sensors.
Designed with an IP68 chemically resistant housing, the sensor supports easy installation via dual 1-inch NPT threaded ports and is adaptable with optional guard caps for anti-fouling, weighted positioning, or air-blast cleaning. Its optical design doesn’t consume oxygen, allowing reliable readings without water flow.
For seamless system integration, it pairs perfectly with the Rosemount 1058 digital transmitter, offering a wide range of output signals to suit varied host systems.
With a compact form factor and high accuracy—±0.1 mg/L (0–20 mg/L) and ±2% (20–60 mg/L)—the Rosemount 490A sets a new standard in digital DO sensing for industries that demand precision, durability, and ease of use.