Chlorine sensor with membrane-covered, amperometric three-electrode system. For the measurement of total chlorine with greatly reduced pH dependence, suitable for seawater.

• Measured variable(s): NaClO (sodium hypochlorite), Ca(ClO)₂ (calcium hypochlorite), Cl₂ (chlorine gas), electrolytically generated chlorine
• Calibration: at the controller, via analytical chlorine determination, DPD-4 method (DPD-1 + DPD-3)
• Interferences: ClO₂ is measured at 100 %, O₃ is measured with a slope of approx. 130 % (factor 1.3 relative to the chlorine slope)
• Resolution: 0.1‒0.001 ppm, depending on the model
• pH range: 4‒12
• Pressure range:
  • 0.5 bar, no pressure surges and/or fluctuations (without securing collar)
  • 3.0 bar, no pressure surges and/or fluctuations (with securing collar)
• Temperature range: 0–45 °C (no ice crystals in the water)
• Sensor with automatic temperature compensation
• Response time: T90 approx. 2 min
• Flow rate: approx. 15‒30 l/h (low flow dependence)
• Shaft length: standard 175 mm (mA version up to 220 mm)
• Connection: standard 4-pin plug; mA version 2-pole terminal, M12 socket or modbus RTU with M12 socket
• Material: microporous hydrophilic membrane, PVC-U, PEEK, stainless steel 1.4571