Turbidity Sensors and Transmitters

Turbidity Sensors and Transmitters

Turbidity measurement systems quantify the cloudiness of water by detecting light scattered or attenuated by suspended particles. A turbidity sensor paired with a transmitter provides continuous indication in standardized units (e.g., NTU/FNU, depending on method) suitable for control, alarming, and reporting. This measurement is central to filtration performance, clarifier optimization, and overall water quality assurance.

The benefit is rapid detection of particulate breakthroughs and process instabilities that affect downstream assets and compliance. Continuous turbidity trends support optimized coagulant dosing, filter backwash timing, and membrane protection by identifying rising solids load before visible quality deterioration occurs. In disinfection contexts, turbidity control also supports effective pathogen control by limiting particle shielding effects.

Sensor designs include nephelometric (90° scatter) methods for low turbidity and absorption/attenuation-based approaches for higher solids ranges. Installation details - flow stability, avoidance of bubbles, and representative sampling - are critical to stable readings. In fouling-prone waters, automatic cleaning (mechanical wipers, air purge, or flushing) can materially reduce drift and maintenance frequency.

Transmitters provide linearization, filtering, diagnostics, and communication interfaces for integration into automation and data historians. Calibration and verification typically use standardized turbidity references and defined procedures to ensure traceability. Diagnostic flags can indicate window fouling, signal saturation, or abnormal optical conditions that compromise measurement quality.

Typical applications include raw water monitoring, coagulation/flocculation control, sedimentation and filtration performance, filter-to-waste transitions, membrane feed protection, and wastewater effluent turbidity verification. Turbidity is also used in industrial utilities and reuse systems where particulate control is linked to equipment protection and product quality. With proper installation and cleaning provisions, turbidity measurement becomes a highly responsive indicator of treatment performance and process stability.

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