Overview
The Rosemount 399-12 pH-201 is an industrial-grade pH sensor equipped with an AccuGlass electrode and 20 feet of integral cable. This sensor is purpose-built for continuous pH monitoring and control in process automation, water treatment, chemical processing, and batch operations. The AccuGlass membrane technology delivers stable, repeatable measurements across a wide pH range, making it a trusted choice for critical industrial applications.
Key Features
- AccuGlass electrode membrane for stable pH measurement and long sensor life
- 20-foot integral cable for extended installation distances
- 1-inch NPT process connection for standard industrial mounting
- Direct process immersion or flow-through cell mounting compatibility
- Integral reference junction for enhanced measurement stability
- Compatible with Rosemount analyzers and third-party pH transmitters supporting standard electrode connections
Technical Specifications
- Model: pH-201
- Electrode Type: AccuGlass (399-12)
- Cable Length: 20 feet integral
- Process Connection: 1-inch MNPT (Male National Pipe Thread)
- Electrode Material: AccuGlass membrane with reference solution ground
- Operating Temperature Range: -10 to 100°C (14 to 212°F) [standard for Model 399 series]
- pH Measurement Range: 0–14 pH
- Typical Response Time: <1 minute for 90% response
- Preamp Configuration: Standard preamplifier (integral or remote)
- Cable Type: Shielded multi-conductor for noise rejection
Typical Applications
- Water treatment and wastewater pH control
- Chemical processing and batch operations
- Food and beverage production
- Pulp and paper manufacturing
- Pool and spa chemistry monitoring
- Cooling tower and boiler feedwater monitoring
- Environmental monitoring and laboratory automation
Compatibility & Replacements
Compatible With
- Rosemount Analytical pH transmitters and analyzers
- Third-party industrial pH/ORP transmitters supporting 1-inch NPT electrode connection
- Remote or integral preamplifier systems with standard preamplifier output
- Handrail and insertion mounting assemblies (separate purchase)
- Process flow cells and tee configurations (1-inch MNPT connection)
Replaces / Drop-In Replacement For
- Rosemount pH-201 variants with different cable lengths
- Direct replacement for other AccuGlass electrodes in 399 series applications requiring 20-foot cable
- Compatible upgrade path from older Rosemount 399 series sensors
Works With
- Rosemount Analytical product suite and HART-compatible transmitters
- Standard 4–20 mA analog output signaling
- Remote preamplifier with up to 3 miles transmission capability (per Rosemount spec)
- Manual and automated sensor maintenance systems (jet spray cleaners, solenoid valve control)
