Chemins Instrument — Online Water Quality Sensors & Monitoring Systems
Hangzhou Chemins Tech designs digital water quality sensors, analyzers, monitoring systems and controllers for municipal water, wastewater, aquaculture and environmental monitoring. Ecotao supplies, configures and supports the full Chemins Instrument range in South Africa.
About Chemins Instrument
Chemins Instrument is the digital water-quality sensor brand of Hangzhou Chemins Tech Co., Ltd., a manufacturer specialising in online sensors, in-situ analyzers, integrated monitoring buoys and micro monitoring stations. The company runs its own production base and two water-quality testing laboratories, and its instruments cover the standard five parameters – conductivity, dissolved oxygen, pH/ORP, turbidity and temperature – along with COD, ammonia nitrogen, total phosphorus, total nitrogen, chlorophyll, blue-green algae and more.
Every sensor and analyzer in the range is built for continuous, unattended field operation: 316L stainless steel or POM housings, IP68 protection on immersion probes, automatic temperature compensation, and RS-485 Modbus RTU output as standard so instruments drop straight into an existing SCADA, PLC or data logger.
Sensor Series
Reagent-free digital probes for continuous immersion or flow-cell monitoring – optical, electrode and fluorescence sensors covering the full spread of water quality parameters, all with automatic temperature compensation and two-point calibration.
Online Full-Spectrum Sensor
Xenon full-spectrum absorption measures COD, TOC, turbidity, BOD, UV254, TP, TN, ammonia nitrogen, nitrate, nitrite and permanganate index from one probe.
- Range: COD 0–200 mg/L, Turbidity 0–400 NTU
- Output: RS-485 Modbus RTU
- Housing: 316L, IP68, immersion
Online pH Sensor
Glass electrode pH sensor with dual high-impedance differential amplification for fast, interference-resistant readings.
- Range: 0–14.00 pH, ±0.1%
- Output: RS-485; 4-20 mA
- Housing: POM / 316L, IP68
Online Dissolved Oxygen Sensor
Fluorescence-based DO measurement – no polarisation or flow-rate requirement, with T98 under 30 seconds.
- Range: 0–20 / 0–50 mg/L, ±2%
- Output: RS-485; 4-20 mA optional
- Housing: 316L, IP68
Online Turbidity Sensor
90° scattered-light turbidity sensor with built-in cleaning brush across four selectable measuring ranges.
- Range: 0–20 up to 0–4000 NTU
- Output: RS-485; 4-20 mA optional
- Housing: 316L, IP68
Online Conductivity Sensor
Electrode-method conductivity sensor with automatic temperature compensation, sized for surface, agricultural and industrial water.
- Range: 0–200 mS/cm, ±1.5%
- Output: RS-485; 4-20 mA optional
- Housing: ABS/316L, IP68
Integrated Multi-Parameter Sensor
One probe body covering up to eight parameters – DO, conductivity, pH, ORP, turbidity, salinity, ammonia nitrogen, COD and more – with automatic cleaning.
- Parameters: Up to 8 simultaneous
- Output: RS-485 Modbus RTU
- Housing: POM/316L, IP68
Online Residual Chlorine Sensor
Constant-voltage residual chlorine measurement for drinking water, pools and disinfection processes, flow-cell mounted.
- Range: 0–2 / 0–20 mg/L (HClO)
- Output: RS-485 Modbus RTU
- Housing: POM/316L, IP68
Online Ammonia Nitrogen Sensor
Ion-selective electrode sensor reporting ammonium, pH, potassium and temperature together for nutrient monitoring.
- Range: NH4+ 0–100 mg/L
- Output: RS-485 Modbus RTU
- Housing: PVC/POM, IP68
Analyzer Series
Wet-chemistry and spectrophotometric analyzers for parameters that need reagent-based accuracy – automatic dosing, calibration and cleaning keep them running unattended for compliance-grade reporting.
Residual / Total Chlorine Analyzer
Spectrophotometric DPD method – free chlorine forms a pink compound read at 515 nm for high-accuracy detection.
- Range: Residual 0–5 mg/L; Total 0–20 mg/L
- Output: RS-485 Modbus RTU
- Protection: IP65, wall-mounted
Cabinet Analyzer Series
Total phosphorus, total nitrogen, ammonia nitrogen, COD and permanganate index analyzers with one-touch self-test and three-year data storage.
- Cycle: 30–41 minutes per test
- Output: RS-485 Modbus RTU
- Features: Auto calibration & cleaning
In-Situ Total Phosphorus Analyzer
Precision optical system deployable directly into buoys, multi-parameter systems, vessels or shore stations for continuous TP monitoring.
- Range: 0–2 / 0–10 mg/L
- Output: RS-485 Modbus RTU
- Protection: IP68, immersion
Monitoring Systems
Integrated stations that combine sensors, power, data logging and remote transmission for unattended deployment at rivers, reservoirs, pipelines and water treatment sites.
Water Supply Monitoring Micro-System
Wall-mounted or floor-standing systems monitoring pH, residual chlorine, conductivity, turbidity and temperature together for drinking-water networks.
- Data: Optional DTU real-time upload
- Protection: IP65 housings
- Deploy: Wall-mount or cabinet
Buoy Monitoring System
Solar-powered floating buoys for rivers, lakes, reservoirs and nearshore waters with 4G data transmission and threshold alarms.
- Sensors: DO, pH, conductivity, turbidity & more
- Power: Solar panel + lithium battery
- Data: 4G, adjustable transmission cycle
Online Monitoring Stations
From compact IP68 underground pipeline units to full chemical-method shore stations for total phosphorus, total nitrogen and COD.
- Deploy: Underground, pole-mounted or shore-based
- Data: Cloud management, warning alerts
- Operation: Unattended, modular expansion
Controller Series
Panel and wall-mounted controllers that display sensor readings, drive alarms and relay data over Modbus – sized to match any Chemins sensor or third-party 4-20 mA probe.
2.8″ Monochrome Controller
Panel-cutout controller with configurable current output and two-channel alarm relay for single-parameter monitoring loops.
- Display: 2.8″ monochrome LCD
- Alarm: 2 channels, AC 250V/3A
- Output: 4-20 mA; RS-485 Modbus
7″ Touchscreen Controller
Colour capacitive touchscreen controller supporting up to six alarm channels for multi-sensor installations and control rooms.
- Display: 7″ colour capacitive touch
- Alarm: 4–6 channels, 10A
- Output: RS-485 Modbus RTU
Compare Core Online Sensors
A quick side-by-side of the most requested Chemins Instrument online sensors.
| Model | Parameter | Range | Accuracy | Output | Housing / Rating |
|---|---|---|---|---|---|
| PHG-406 | pH | 0–14.00 | ±0.1% | RS-485; 4-20 mA | POM/316L, IP68 |
| RDO-406 | Dissolved oxygen | 0–20 / 0–50 mg/L | ±2% | RS-485; 4-20 mA optional | 316L, IP68 |
| ZS-408 | Turbidity | 0–20 to 0–4000 NTU | ±3–5% | RS-485; 4-20 mA optional | 316L, IP68 |
| DDM-406 | Conductivity | 0–200 mS/cm | ±1.5% | RS-485; 4-20 mA optional | ABS/316L, IP68 |
| CL-406 | Residual chlorine | 0–2 / 0–20 mg/L | ±5% or ±0.05 mg/L | RS-485 Modbus RTU | POM/316L, IP68 |
| NHN-407C | Ammonia nitrogen | 0–100 mg/L | ±10% | RS-485 Modbus RTU | PVC/POM, IP68 |
| FUV-408 | COD, TOC, turbidity & more | COD 0–200 mg/L | ±5% F.S. | RS-485 Modbus RTU | 316L, IP68 |
Applications
How to Choose
Identify the parameters
Decide whether you need one parameter (pH, DO, turbidity) or several at once – multi-parameter sensors and analyzers cover both.
Match the deployment
An immersion sensor suits an existing tank or channel; a monitoring system or buoy suits sites with no fixed structure at all.
Check the installation
Match the sensor to how it will sit in the water – immersion, flow cell, pipeline or buoy – and confirm NPT thread size.
Plan the data path
Decide if readings need to reach a PLC/SCADA over RS-485 or 4-20 mA, or upload remotely via a DTU or 4G buoy system.
Confirm maintenance
Reagent-free sensors need only periodic calibration; reagent-based analyzers need dosing and cleaning cycle planning.
Frequently Asked Questions
Sensors are reagent-free digital probes (optical, electrode or fluorescence based) that mount directly in water for continuous monitoring. Analyzers use standard wet-chemistry or spectrophotometric methods with reagents for parameters such as total phosphorus, total nitrogen and residual chlorine, giving lab-grade accuracy for compliance reporting.
Yes. Most sensors, analyzers and controllers output RS-485 Modbus RTU, and many also support 4-20 mA, so they connect directly into PLCs, SCADA systems, chart recorders and touch panels already on site.
The optical and electrode sensors in the Sensor Series are reagent-free and only need periodic two-point calibration. The Analyzer Series and cabinet analyzers use small reagent volumes with automatic dosing, calibration and cleaning cycles.
The MF-520 and MF-610 buoys are solar-powered floating units for rivers, lakes and reservoirs, anchored in place with 4G data transmission. Shore-based and pole-mounted stations (MS-500, MS-800, MS-900) sit on the bank or a fixed structure and pump or draw water to the instrument, suiting sites where a permanent structure is available.
Talk to Ecotao about Chemins Instrument
Not sure which sensor, analyzer or monitoring system fits your site? Send us your application and we'll put together a spec.