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CL17 Free Chlorine Analyzer


Industry standard, CL17 Free Chlorine Analyzer. Included with the CL17 analyzer is a 1 month supply of DPD indicator and Free Chlorine indicator and buffer solutions, an installation kit, sample conditioning kit, maintenance kit, and a user manual.

Accurate, Reliable Results

The Hach CL17 Chlorine Analyzer uses colorimetric DPD chemistry to monitor water continuously for free or total residual chlorine. The CL17 is a simple, dependable and economic solution, and the preferred choice to high-maintenance instruments that require frequent calibration. The CL17 analysis method is robust and not affected by changes in chlorine concentration, sample pH, temperature, flow, or pressure, thus offering more accuracy and reliability than alternative instruments and technologies.

Simple, Predictable Maintenance

Monthly routine maintenance for the CL17 can typically be performed in 15 minutes and includes changing reagents and cleaning the colorimetric cell. No special tools are required. For typical use, the CL17 will operate unattended for 30 days. Challenging applications may require more frequent cleaning.

Factory Calibrated

The CL17 Chlorine Analyzer is factory calibrated. A built-in electronic calibration curve is preprogrammed into the instrument. This instrument does not require recalibration unless specified by your regulatory agency for compliance reporting purposes.

EPA Compliant

The CL17 is compliant with US EPA regulation 40 CFR 140.74, and both Method 4500-CL G and Method 334.0 can be used for measurement of residual chlorine in drinking water.

Pump Control

Both an alarm for manual chlorine feed control and a 4-20 mA output for automatic control of chlorine feed pumps is available on the CL17 Analyzer.




0 to 5 mg/L free or total residual chlorine


± 5 % or ±0.03 mg/L (ppm) as CL2, whichever is greater

Pressure Limit:

Inlet Pressure to Sample Conditioning: 1.5 to 75 psi (0.1 bar to 5.2 bar)

Sample Flow Rate:

200 to 500 mL per minute minimum required

Lower Limit of Detection (LOD):

0.03 mg/L (ppm)

Cycle Time:

2.5 minutes

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