WTW Turb PLUS 2000 Online Turbidimeter

Overview

The WTW Turb PLUS 2000 is a high-precision online turbidimeter engineered for continuous, real-time monitoring of turbidity in water and wastewater treatment processes. It operates on the principle of infrared (IR) nephelometry at 860 nm, conforming strictly to ISO 7027 and U.S. EPA Method 180.1—ensuring metrological traceability and regulatory acceptability across global drinking water and environmental compliance frameworks. Unlike portable or benchtop units, the Turb PLUS 2000 is designed for permanent installation in pressurized or gravity-fed process streams, delivering stable, drift-free measurements under dynamic hydraulic conditions. Its optical architecture features a dual-detector configuration with temperature-compensated LED excitation and optimized light path geometry to minimize stray light interference and enhance signal-to-noise ratio—critical for achieving sub-milliturbid unit resolution in low-turbidity applications such as finished drinking water.

Key Features

• Triple-range capability: factory-configured 0–100 NTU, plus user-selectable 0–10 NTU and 0–1000 NTU ranges loaded via USB—enabling optimal sensitivity across source water, clarifier effluent, and filtered water streams.
• Resolution down to 0.0001 NTU in the 0–10 NTU range—supporting stringent regulatory thresholds (e.g., <0.1 NTU or <1.0 NTU at plant discharge per WHO and EU Drinking Water Directive requirements).
• Integrated ultrasonic transducer system for automated optical window cleaning—reducing maintenance frequency and eliminating manual wiping or chemical cleaning cycles without interrupting measurement continuity.
• Rugged stainless steel (1.4404 / SS316L) wetted housing rated IP68 and suitable for submersion up to 10 m depth or inline mounting in DN50–DN150 pipelines with optional flow cells.
• Dual-output interface: isolated 4–20 mA current loop for PLC/SCADA integration and RS-485 serial communication supporting Modbus RTU protocol for bidirectional data exchange and remote configuration.
• Fully compatible with WTW’s IQ Sensor Net platform via MIQ transmitter modules or IC2 interface—enabling centralized calibration management, firmware updates, and multi-parameter synchronization (e.g., combined turbidity + pH + chlorine monitoring).

Sample Compatibility & Compliance

The Turb PLUS 2000 is validated for use with potable water, surface water, groundwater, secondary effluent, and membrane filtrate—covering all critical control points from intake to distribution. Its IR-based optical design minimizes color interference and eliminates spectral bias associated with white-light turbidimeters, making it especially suitable for humic-rich or iron-stained waters. All measurement algorithms and calibration routines adhere to ISO/IEC 17025-aligned validation protocols. The device supports GLP-compliant audit trails when integrated into IQ Sensor Net systems, including timestamped calibration logs, sensor diagnostics, and cleaning event records—fully traceable for FDA 21 CFR Part 11 and EU Annex 11 readiness. Regulatory alignment includes full conformance with German Trinkwasserverordnung (TrinkwV), U.S. EPA Surface Water Treatment Rule (SWTR), and WHO Guidelines for Drinking-water Quality (4th ed.).

Software & Data Management

Data acquisition and system management are handled through WTW’s proprietary MultiLine software (v4.0+) and cloud-enabled IQ Sensor Net infrastructure. The instrument stores up to 10,000 timestamped readings internally with configurable logging intervals (1 s to 24 h). Calibration is performed using certified formazin or AMCO-AE standards traceable to NIST SRM 2100 series, with up to three-point calibration support (zero, mid, high) and automatic slope/offset verification. Firmware updates are delivered over USB or remotely via IQ Sensor Net, ensuring long-term compliance with evolving method revisions. All data exports comply with CSV and XML formats for LIMS integration, and Modbus register mapping enables direct mapping into Siemens S7, Rockwell ControlLogix, or Schneider EcoStruxure platforms without middleware.

Applications

• Drinking water treatment: Real-time monitoring at rapid sand filter effluent, final clearwell outlet, and distribution system entry points—ensuring compliance with <1.0 NTU (or <0.1 NTU where ultrafiltration is employed) as mandated by national regulations.
• Sedimentation control: Feedback signal for optimizing coagulant dosing and flocculation time based on post-sedimentation turbidity trends—reducing chemical consumption while maintaining particle removal efficiency.
• Membrane integrity assurance: Early detection of microfiltration/ultrafiltration breakthrough events through sustained turbidity increases >0.05 NTU above baseline—triggering automated integrity test sequences.
• UV disinfection validation: Correlation of turbidity with UV transmittance (UVT) to dynamically adjust lamp intensity and residence time—maximizing pathogen inactivation while minimizing energy use.
• Wastewater reuse: Monitoring tertiary effluent prior to irrigation or industrial reuse—meeting ISO 16075 and California Title 22 Class A criteria.

FAQ

Does the Turb PLUS 2000 require periodic recalibration?
Yes—calibration frequency depends on application severity. For drinking water applications, WTW recommends quarterly two-point (zero and span) calibration using traceable standards; for high-fouling environments, monthly verification is advised. Full calibration logs are retained in internal memory and exportable.

Can the instrument operate in pressurized pipelines without a flow cell?
No—it must be installed in conjunction with a WTW-certified flow-through cell (e.g., FC100 or FC200 series) to ensure laminar flow, consistent optical path length, and pressure equalization. Direct insertion into unregulated mains is not supported.

Is the ultrasonic cleaning function programmable?
Yes—cleaning interval, duration, and trigger threshold (e.g., signal attenuation >5%) are fully configurable via MultiLine software or IQ Sensor Net web interface.

What is the maximum allowable suspended solids concentration for reliable operation?
The Turb PLUS 2000 maintains accuracy up to 1000 NTU; however, for samples exceeding 200 mg/L total suspended solids (TSS), particulate settling or clogging risk increases—requiring upstream filtration or dilution protocols aligned with ISO 7027 Annex B guidance.