Typical Water Applications for Residual Chlorine Sensors
RS485 residual chlorine sensors are widely used in online water disinfection control across these scenes:
- Drinking water & municipal tap water (water plants, pipe networks, secondary water supply)
- Swimming pools & spa water (commercial pools, water parks, hotels)
- Wastewater treatment (municipal sewage, industrial effluent disinfection)
- Circulating cooling water & process water (food & beverage, pharmaceutical, electronics)
- Hospital wastewater & disinfection water
These scenarios need
stable, long‑term online
residual
chlorine monitoring with RS485 Modbus output for PLC, SCADA, and IoT platforms.
Two Core Measurement Principles
1. Membrane Method (Amperometric Membrane Electrode)
The sensor uses a
hydrophobic selective
membrane to let only free chlorine pass through while blocking impurities.
Chlorine reacts inside the electrode, generating a current proportional to concentration.
2. Constant Voltage Method (Polarographic / Three‑Electrode Constant Potential)
A
three‑electrode structure maintains a stable potential between working and reference electrodes.
No membrane or electrolyte is needed; chlorine reacts directly on the electrode surface.
Which to Choose: Membrane or Constant Voltage?
Membrane Method Best For
- Swimming pools (resists urea, sweat, organic interference)
- High‑precision drinking water
- Water with moderate suspended solids
- Projects needing stable, accurate long‑term measurement
Constant Voltage Method Best For
- Clean tap water & pipe networks
- Low‑maintenance industrial circulating water
- Simple installation with no electrolyte refilling
- Harsh water that easily clogs membranes
Pros & Cons Comparison
|
Item
|
Membrane Method
|
Constant Voltage Method
|
|
Accuracy
|
High, better anti‑interference
|
Good, slightly lower in dirty water
|
|
|
Needs electrolyte & membrane replacement
|
Low maintenance, only clean electrodes
|
|
Lifespan
|
Medium (consumable parts)
|
Longer (no consumables)
|
|
Response
|
Moderate
|
Fast (10–30 seconds)
|
|
Installation
|
Flexible (immersion / flow‑through)
|
Mostly flow‑through
|
|
Price
|
Higher
|
Lower
|
|
Best Scene
|
Pools, precision drinking water
|
Clean tap water, low‑maintenance systems
|
Why RS485 Residual Chlorine Sensor?
- Digital RS485 (Modbus-RTU) output for easy system integration
- Stable signal, strong anti‑interference for industrial sites
- Supports remote monitoring & automatic dosing control
- IP68 industrial design for long‑term field use
Final Selection Suggestion
- Choose membrane‑type RS485 residual chlorine sensor for swimming pools, high‑precision drinking water, or complex water quality.
- Choose constant voltage RS485 residual chlorine sensor for clean tap water, circulating water, or low‑maintenance projects.
If you need
online
residual
chlorine analyzer,
digital water quality sensor, or
RS485 water monitoring solution, our full series supports OEM/ODM and global delivery.
