Cl · Free Chlorine Sensor

M200 Free Chlorine Digital Sensor

Membrane or constant-voltage measurement tracks hypochlorous acid and free chlorine from 0.00 to 20.00 mg/L with ppb-level resolution. Automatic temperature compensation, IP68 protection, flexible installation, and RS485 output support precise chlorination control.

product image ·
20 mg/L
Max Range
10 ppb
Resolution
90 s
Response Time
IP68
Full protection · RS485
Features

Precise free-chlorine control for safer disinfection

The membrane method is reagent-free, while the constant-voltage design uses a stable dual-platinum ring. Both provide ppb-level resolution for accurate, closed-loop chlorination with lower chemical use.

Advanced Circuitry

High-impedanceMeasurement ,ppb Free ChlorinesignalHigh-precision Acquisition,Anti-interference.

Easy Installation

Submersion and flow-through options with a standard 5 m cable for quick deployment.

Industrial-grade Protection

IP68 protection with PC and stainless-steel or ABS housing options.

Fast Response

Reaches 90% of final value within 90 seconds, auto temperature compensation, stable readings.

Model Selection

Cl Sensor Model Overview

The series supports multiple installation methods and water types. Filter by installation method, then add a model to your selection list or contact our engineers for verification.

M200-CL-01
RS485 Digital
Submersion · Membrane MethodGeneral
Range0–20 mg/L
Measurement PrincipleMembrane Method
Temp. Range0–60°C
Housing MaterialPC+Stainless Steel
Tap WaterDisinfectionMunicipal
M200-CL-02
RS485 Digital
Flow-through · Membrane MethodOnline
Range0–20 mg/L
Measurement PrincipleMembrane Method
Temp. Range0–60°C
Housing MaterialABS
Secondary SupplyCirculating Waterswimming pool
M200-CL-03
RS485 Digital
Flow-through · Constant Voltage
Range0–20 mg/L
Measurement PrincipleConstant Voltage(Dual Platinum Ring)
Temp. Range0–60°C
Housing MaterialABS
Tap Water PlantReverse-osmosis influentIndustrial Processes
M200-CL-04
4-20mA Analog
Submersion · Membrane MethodPressure-resistant
Range0–20 mg/L
Measurement PrincipleMembrane Method
Temp. Range0–60°C
Housing MaterialPC+Stainless Steel
Clear Water TankElevated TankWater Supply
M200-CL-05
RS485 Digital
Flow-through - Smart Constant Voltage
Range0–20 mg/L
Measurement PrincipleConstant Voltage(Dual Platinum Ring)
Temp. Range0–60°C
Housing MaterialABS
swimming poolLandscape WaterCirculating Water
M200-CL-06
RS485 Digital
Flow-through - Low Range
Range0–2 mg/L
Measurement PrincipleMembrane Method
Temp. Range0–60°C
Housing MaterialABS
Pure water disinfectionDrinking WaterReverse Osmosis
Specifications

Complete Specifications

General specifications for the series. Range, housing, and output vary by model and are confirmed during selection.

Measured Parameter
Free Chlorine / Hypochlorous Acid (HOCl)
Measuring Range
0.00–20.00 mg/L(ppm)
Measurement Principle
Membrane Method / Constant Voltage(By Model)
Measurement Accuracy
2% ±10 ppb HOCl
Temp. Compensation
Automatic
temperatureSensor
NTC22K(Optional PT100 / PT1000)
Temp. Measurement range
0.0–60.0°C
Response Time
Reaches 90% of final value within 90 seconds
Flow Velocity
15–30 L/h
Calibration Method
laboratory
Pressure Range
0–1 bar
Housing Material
PC+Stainless Steel / ABS(By Model)
Cable Length
Standard 5m (Customizable)
Protection Rating
IP68
Electrical Connection
RS485 (MODBUS-RTU) or 4-20mA Analog
Installation
Submersion / Flow-through
Warranty
1 year
Applications

Suitable Water Types

Free chlorine is a key indicator of disinfection in drinking water and industrial processes. Online monitoring enables precise, closed-loop chlorination. Select the measurement principle and housing for your water type below.

Water supply andDisinfection

5
Drinking WaterDisinfectionTap Water PlantSecondary SupplyClear Water TankReverse-osmosis influent

Municipal & Environmental

4
Municipal wastewaterLandscape WaterRiver Replenishmentreclaimed water reuse

Industrial Processes

4
petroleumChemicalPowerPharmaceuticalFood

Circulation & Venues

3
swimming poolCooling Tower WaterWater Park
Get a recommendation

Tell us your water type and installation method, and we will recommend the right free-chlorine model

Send us the free-chlorine range, water type, and installation conditions. Our engineers will recommend the measurement principle, housing, output, and installation for your application.