Target and method
Confirm the disinfectant and whether the required result is free chlorine, total chlorine, chlorine dioxide or active oxygen before choosing colorimetric or electrochemical measurement.
CL₂ / ClO₂ · Online disinfectant monitoring
Select free- and total-chlorine measurement by disinfectant, result and water matrix
Five analyzers now have independent records from their supplied sheets, covering DPD colorimetry, constant-voltage amperometry, micro-MEMS and membrane electrodes. Similar ranges do not make them interchangeable.
5verified product detail pages
4measurement approaches
0.005 mg/Llowest documented detection limit
3real project records
01 · Start with the target
Separate free chlorine, total chlorine, chlorine dioxide and active oxygen first
Target species, water chemistry, range, maintenance method and control interfaces must be confirmed together.
Range and detection limit
Provide normal, peak and alarm values plus the lowest concentration that must be identified.
Water and flow cell
Confirm pH, conductivity, temperature, pressure, flow, sample cleanliness and possible interferents.
Maintenance and interface
Confirm reagent, membrane, calibration interval, power, 4–20 mA, relays and Modbus.
02 · Model architecture
Five online disinfectant analyzers
Each detail page retains its own original range, accuracy, sample limitations, dimensions and interface evidence.
DPD colorimetric analyzerCL-201Free / Total Chlorine and Active Oxygen Analyzer
A reagent-based online analyzer for applications that require documented free chlorine, total chlorine or active-oxygen measurement with automatic cleaning and configurable operating modes.
DPD colorimetry0–20 mg/L total chlorine7-inch touchscreen
Constant-voltage amperometric analyzerPDCL-400Free Chlorine / Chlorine Dioxide Analyzer
A clean-water flow-cell configuration using constant-voltage amperometric measurement and a replaceable 316 stainless-steel electrode.
0–2 / 0–20 mg/LpH 5–830–60 L/h
Micro-MEMS electrochemical analyzerPDCL-500MFree Chlorine / Chlorine Dioxide Analyzer
A compact electrochemical sensor for treated water, rural drinking-water and secondary-supply projects where conductivity and pH remain inside the documented limits.
0–2 / 0–5 mg/L0.01 mg/L≥100 µS/cm
Covered-membrane three-electrode analyzerPDCL-700Online Free Chlorine Analyzer
A covered-membrane three-electrode configuration designed to reduce the effect of pH variation and support drinking water, secondary supply, heating, circulating and cooling-water monitoring.
0.05–20.00 mg/LpH 4–9IP68 sensor
Composite digital membrane analyzerPDCL-600Free / Total Chlorine and Chlorine Dioxide Analyzer
The broadest documented disinfectant range in this five-model family, using a composite digital membrane electrode with no routine zero calibration and DPD-1 slope calibration.
0.5–200 mg/LpH 4–9DPD-1 slope calibration
03 · Applications
Three real online chlorine projects
Chinese information panels have been removed from public images. English-site background, configuration and results are searchable English web copy.
View full cases↗
2021 · Liangshan, Sichuan, ChinaWater-plant inlet and outlet chlorine monitoring
In June 2021, flow measurement and online analyzers were installed at inlet and outlet points so operators could identify water-quality risks and review disinfection performance continuously.
Monitored parametersFree chlorinepHSuspended solidsChlorine dioxideFlow
↗
2022 · Wuhan, Hubei, ChinaSecondary water-supply residual-chlorine monitoring
In September 2022, an online analyzer was installed to track free chlorine in the secondary-supply pipeline continuously and provide timely visibility of disinfectant residual.
Monitored parametersFree chlorinePipeline flow-cell conditions4–20 mA signal
↗
2023 · ChinaIntegrated county water-supply monitoring platform
In April 2023, pipeline monitoring was installed to combine pH, turbidity, dissolved oxygen, conductivity and residual chlorine for routine inlet, outlet and distribution-water checks.
Monitored parametersFree chlorinepHTurbidityDissolved oxygenConductivity
↗04 · Common questions
Confirm this information before an inquiry
How do I choose DPD colorimetry or an electrochemical method?+
Colorimetry directly follows a specified reagent reaction. Electrochemical methods support continuous measurement but depend more heavily on pH, conductivity, flow or membrane conditions.
Can I select only by maximum range?+
No. Detection limit, normal value, sample conditions, maintenance and control interfaces also matter.
Can PDCL-500M measure ultrapure water?+
No. Its supplied sheet requires conductivity of at least 100 µS/cm.
Can the image replace a dimensional drawing?+
No. Clean images are for public presentation; mounting and accessories come from the datasheet and project confirmation.
Contact FUNEL
Tell us what you need to measure.
We will respond with a recommended configuration, supporting documentation and quotation.