Electrochemical chlorine sensor AS2

for water treatmentfor process controlIP65

Product description
The German-made amperometric potentiostatic three-electrode sensor AS2 provides continuous measurement of free chlorine in drinking water and standard process water. Designed for standard environments (measuring water ≤50 °C), it operates without membrane or electrolyte enabling indefinite dry storage. The PVC-U housing and multiple electronic interface options simplify integration and spare-part management for municipal and industrial water systems.

Special features

• Operates at elevated pressures (up to 8 bar with retaining ring)
• Short response time (T90 ≈ 30 s)
• Tolerant to surfactants
• Reduced maintenance with optional automatic electrode cleaning (RV1)

Applications

• Municipal drinking water monitoring and control
• Standard process water treatment in industrial and utility plants

Process conditions

• Stable pH required (approx. pH 5–9)
• Max. measuring water temperature: 50 °C (no ice crystals in the measuring water)
• Max. ambient temperature: 55 °C
• Max. operating pressure: up to 8 bar (installation dependent)

Technical specification (summary)

• Model: AS2
• Measured parameter: Free chlorine (amperometric, potentiostatic 3‑electrode system)
• Measuring ranges / resolution: selectable ranges e.g. 0.005–2.000 ppm (0.001 ppm); 0.03–20.00 ppm (0.01 ppm); 0.5–200.0 ppm (0.1 ppm)
• Response time: T90 ≈ 30 s
• Measuring water temperature: 0 … +50 °C
• Ambient temperature: 0 … +55 °C
• Temperature compensation: automatic (integrated sensor, response t90 ≈ 10 min; avoid sudden changes >30 °C/h)
• Max. working pressure: up to 8 bar with retaining ring (no pressure surges/vibrations)
• Flow rate (face velocity): without RV1 min. 15 l/h; with RV1 45–90 l/h
• pH range: 5–9
• Run-in time: approx. 1 hour to 2 days (depends on water quality)
• Zero point adjustment: not required
• Protection: IP68 (5‑pole M12 plug) / IP65 (2‑pole terminal)
• Housing material: PVC‑U