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Residual chlorine monitor with PID

Residual chlorine is one of the most important measurements for the effective monitoring of cooling, potable and industrial water treatment processes. The AW402 residual chlorine monitor control and monitors residual chlorine levels accurately and affordably.

Brochure: Serving the world's water industries

Proven measurement solutions and trusted application expertise throughout the entire water cycle



The AW402 design enables connection of up to 3 residual chlorine monitoring sensors to the system or enables pH, ORP and residual chlorine sensors to be combined, thus reducing the cost of each measurement considerably


  • Total and free residual chlorine measurement – add potassium iodide to reagent to convert free chlorine measurement to total chlorine
  • Reagentless operation – reduced operating costs with reagentless operation at a pH of 7.5 or less
  • Multiple sensor input capability – reduced installation costs for multiple point monitoring operations
  • Self-cleaning sensor assembly – prolongs sensor life and maintains accuracy


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