Leici WZT-701 Online Turbidimeter

Overview

The Leici WZT-701 Online Turbidimeter is an industrial-grade, continuous-process turbidity monitoring instrument engineered for reliable, long-term deployment in municipal water treatment, drinking water distribution networks, surface water quality surveillance, and process water loops within pharmaceutical, food & beverage, and power generation facilities. It operates on the principle of nephelometric measurement—detecting scattered light intensity at a 90° angle relative to an incident near-infrared (NIR) LED beam—conforming to ISO 7027-1:2016 and EPA Method 180.1 for standardized turbidity quantification in NTU (Nephelometric Turbidity Units). Unlike benchtop or portable units, the WZT-701 integrates directly into pressurized or gravity-fed piping systems via standardized 1/2″ NPT or DIN 11851 sanitary fittings (adapter kits optional), enabling real-time, flow-through analysis without sample diversion or manual intervention.

Key Features

• High-stability NIR light source with temperature-compensated photodetector array ensures consistent signal integrity across ambient fluctuations (0–40 °C operating range).
• Large dot-matrix LCD display simultaneously presents real-time turbidity (NTU) and integrated Pt100 temperature reading—critical for temperature-corrected reporting per ISO 7027 Annex B.
• Dual-resolution mode: 0.01 NTU resolution below 10 NTU (optimized for potable water compliance), switching automatically to 0.1 NTU above 10 NTU for robustness in high-turbidity industrial effluents.
• Configurable 4–20 mA analog output with fully programmable zero/span mapping—supports integration into DCS, SCADA, or PLC systems with HART-compatible signal conditioning.
• RS-232 serial interface enables direct connection to local data loggers or supervisory PCs for periodic configuration updates and historical trend export (ASCII or CSV format).
• IP65-rated aluminum alloy enclosure provides dust-tight and water-jet resistant protection—suitable for installation in pump stations, chlorination rooms, and outdoor kiosks without additional weatherproof housing.
• Non-volatile EEPROM retains calibration coefficients, alarm thresholds, and system parameters through power cycles; automatic power-fail recovery preserves operational continuity.

Sample Compatibility & Compliance

The WZT-701 is validated for use with clear to moderately turbid aqueous matrices including treated drinking water (target range: 0.05–5 NTU), raw surface water (up to 500 NTU), cooling tower make-up, and low-solids process streams. It is not recommended for highly colored, emulsified, or suspended particulate-laden samples (e.g., wastewater influent >1000 NTU, slurry suspensions) without inline filtration or dilution preprocessing. The instrument meets electromagnetic compatibility requirements per IEC 61326-1:2021 (industrial environment class) and electrical safety standards per IEC 61010-1:2010. While not certified to UL/CE for hazardous locations, its design supports integration into water utility infrastructure compliant with ANSI/AWWA B100-22 (turbidity monitoring in distribution systems) and EU Drinking Water Directive (2020/2184) Annex I parameter monitoring protocols.

Software & Data Management

No proprietary PC software is bundled; configuration and diagnostics are performed via terminal emulation (e.g., PuTTY, Tera Term) over RS-232 using documented ASCII command set (AT-style syntax). All critical parameters—including calibration date, reference standard values (e.g., Formazin or AMCO-AE traceable standards), alarm hysteresis, and output scaling—are stored with timestamped audit trails in non-volatile memory. For regulated environments (e.g., FDA-regulated pharmaceutical water systems), users may implement external validation protocols aligned with 21 CFR Part 11 requirements by logging all configuration changes through a validated SCADA historian with electronic signature capability. Firmware updates are performed via serial bootloader and require physical access—no remote update functionality is implemented, minimizing cybersecurity exposure.

Applications

• Real-time monitoring of filter effluent turbidity in conventional and membrane-based drinking water plants (alerting on breakthrough events per AWWA Standard G300).
• Verification of coagulation/flocculation efficiency during pilot-scale optimization studies.
• Continuous surveillance of reservoir intake water quality to trigger early-warning responses to algal blooms or sediment resuspension.
• In-line verification of final rinse water clarity in sterile pharmaceutical component cleaning validation (supporting USP <1231> purified water specifications).
• Process water turbidity trending in semiconductor fab ultrapure water (UPW) sub-loops where particle counts correlate strongly with NTU deviations.

FAQ

Does the WZT-701 support automatic temperature compensation?

Yes—integrated Pt100 sensor enables real-time NTU correction per ISO 7027-1 Annex B algorithms, with user-selectable compensation ON/OFF.
Can it be calibrated with non-Formazin standards such as StablCal or AMCO-AE?

Yes—the two-point calibration routine accepts any traceable NTU standard; users must input certified reference values manually.
Is the 4–20 mA output intrinsically safe?

No—it is isolated but not intrinsically safe; external barriers are required for Zone 1/2 hazardous area installations.
What maintenance intervals are recommended for field operation?

Optical window cleaning every 7–14 days in high-fouling applications; annual verification against certified standards per ISO/IEC 17025 accredited lab procedures.
Does the device store historical turbidity readings internally?

No—internal memory retains only configuration and calibration logs; continuous data logging requires external SCADA or PLC integration.