Sludge Concentration Sensor

I. Application

The HD-DJ11S online sludge concentration sensor measures the sludge concentration in water using the scattering or absorption characteristics of light. With high sensitivity, fast response and real-time monitoring capability, it is widely used in water quality monitoring and wastewater treatment.

An automatic cleaning wiper effectively prevents biological fouling and keeps the optical window clean, ensuring stable long-term monitoring data.

II. Key Features

1. RS485 (MODBUS-RTU) signal output with an infrared LED light source for strong interference immunity.

2. Measuring range 0–20.000 g/L with a resolution of 0.001 g/L.

3. Built-in automatic cleaner prevents biological attachment and optical window fouling; the cleaning time and number of cleaning cycles are configurable.

4. Internal signal isolation technology for strong interference immunity.

5. Good reproducibility, thermal stability and low drift, with a compact body and fast response.

6. 3/4 NPT pipe thread for simple immersion mounting, with stable performance and long service life.

7. IP68 waterproof rating.

III. Technical Parameters

IV. Installation and Wiring

Keep at least 5 cm from the side wall and 10 cm from the bottom.

The cable is a 4-core shielded cable: red - power supply (12–24 VDC), blue - ground (GND), green - RS485-B, yellow - RS485-A. Check the wiring order carefully before powering on, to avoid unnecessary losses caused by incorrect connection. Cable colours may differ slightly between production batches; the colour print on the cable always prevails.

V. Maintenance and Care

The measuring window is the key component that ensures correct operation and accurate measurement, so keeping it clean is essential. Clean the window periodically to remove dirt, deposits and other contaminants; the interval depends on the measuring environment, but daily or weekly cleaning is recommended. Use a mild detergent only - never abrasive, acidic or alkaline cleaners. Wipe the surface gently with a soft cloth or sponge, avoid touching it with bare hands so as to keep fingerprints and grease away, rinse thoroughly with clean water and dry with a soft dry cloth. Check the window regularly for damage or wear, and never expose it to aggressive chemicals or high temperatures. The window contains glass, so never scrape it with sharp or hard objects. The sensor contains sensitive optical components and precision electronics; protect it from violent vibration and impact. Fit the dust cap when the sensor is not in use. When measurement error appears after long service, recalibrate the sensor with a host instrument; if calibration and measurement are still impossible after maintenance, the sensor has failed and should be replaced.