Q46H/62-63 Residual Chlorine Monitor

ATi’s Residual Chlorine Monitor provides easy online monitoring and control of chlorination systems, with minimal maintenance.

Continuous water quality monitoring of Residual Chlorine

ATi’s Residual Chlorine Monitor is an upgraded version of our proven Q45H system for continuous water quality monitoring of free or combined chlorine.

Monitor capabilities have been expanded to include options for a 3rd analog output or for adding additional low power relay outputs. Digital communication options for Profibus DP, Modbus RTU or Ethernet IP have been added, as well. The Q46H system uses a polarographic membraned sensor to measure chlorine directly, without the need for chemical reagents and an automatic pH compensation may be added for highest free chlorine measurement accuracy.

Q46H systems are economical to purchase, economical to maintain and provide long term accuracy and reliability for your chlorine monitoring needs.

Features & specifications

  • Offers Free or Combined Chlorine measurement
  • Economical Operation
  • Automatic pH Compensation
  • Dual Chlorine/pH Monitoring
  • Programmable range options from 0-200 PPB up to 0-200 PPM provide maximum application flexibility.
  • AC or DC Power Options
  • Two isolated 4-20 mA outputs are standard, with an option for a third output if required. Default setting provides analog outputs for chlorine and pH.
  • Standard PID control function assignable to one analog output.
  • Available in either Profibus-DP, Modbus-RTU or Ethernet-IP.
  • Three SPDT relays are standard, with relay functions programmable for alarm, control, or trouble indication. Three additional low power relays available as an option.
  • NEMA 4X (IP-66) enclosure is suitable for wall, pipe, or panel mounting.
  • Back-lit large LCD display provides clear visibility in any lighting conditions. A scrolling second line on the display provides additional information and programming prompts.


The Q46H/62-63 Residual Chlorine Monitor is available for a wide range of applications including:

  • Potable water systems
  • Water reuse systems
  • Cooling towers
  • Aquariums
  • Wastewater treatment effluents.

Key benefits

  • Free or combined chlorine
  • Automatic pH compensation
  • Reagent free
  • Dual Chlorine/pH Monitoring



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