The right Chlorine Monitor for
your application

We supply the most reliable and cost efficient instrument for monitoring residual chlorine. Colorimetric DPD chemistry technology provides a proven, stable, and reliable reading along with the most economical method available.

Chlorine Monitor



CL720 The Lucenline CL720 Free/Total residual Chlorine Monitor is an accurate, economical and low maintenance instrument for chemical and industrial processes or municipal applications that require continuous monitoring and control of residual Free or Total Chlorine levels. Users can select 4-20mA and RS-485 cycle times with Modbus output to control feed pumps and user selectable alarms allow complete manual or automatic control of chlorine dosing. The instrument is housed in a strong shatterproof case with easy access to all service functions and reagents.


Range 0 - 10 mg/l
Cycle Time User selectable: 110 seconds to 10 minutes
Accuracy 0 - 6 mg/l:±5% or 0.03 mg/l of Cl2 whichever is greater
6 - 10 mg/l:±10%
Resolution 0.01 mg/l
Method USEPA accepted DPD method of analysis for measuring Free or Total Residual Chlorine
Power 100 - 240 volt auto switchable 47-63Hz
Standard Output 4-20 mA and RS-485 with Modbus
User alarms 2 user selectable alarms for sample concentration (Form C 240VAC 2A)
Input Pressure 5 - 150psi (0.3bar-10.3bar)
Enclosure ABS Plastic, NEMA 4X, IP66
Installed Dimensions 12.82" x 12.25" x 5.06"
Shipping Dimensions 16" x 16" x 10" (41cm x 41cm x 26cm)
Net Weight 6 lbs (2.7kg)
Shipping Weight 8 lbs (3.6kg)
Flow Rate to Waste 200-400 ml/min
 Ambient Conditions
Operating Temperature of CL720 0° - 55°C
Operating Temperature for 30-day Reagent Life 0° - 40°C, Reagent life will be <30 days operating above 40°C


  • Free or Total Chlorine measurements
  • Low reagent use, low operating costs
  • Simple operation, designed for unattended operation up to 30 days
  • USEPA accepted methodology. Standard method 4500-Cl G, DPD colorimetric method
  • Colorimetric DPD chemistry. Uses inexpensive DPD chemistry rather than expensive electrodes
  • User selectable cycle times: 110 seconds - 10 minutes (optional 60 seconds - 10 minutes)
  • Microprocessor based technology ensures high quality at a low price
  • Two user selectable alarms for sample concentration
  • 4-20mA and RS-485 with Modbus

Address: 11111 Katy Freeway, Suite 910, Houston, TX 77079 USAPhone: +1-832-380-8855Fax: +1-832-380-8866Email: