GDYS-101SB Colorimeter by Jilin University–Xiaotianshe

Overview

The GDYS-101SB Colorimeter is a portable, field-deployable optical instrument engineered for rapid, quantitative determination of color in water samples according to the Chinese national standard GB/T 5750.4–2006 (Methods for Examination of Drinking Water – Sensory Characteristics and Physical Parameters). It operates on the principle of absorbance photometry at a fixed wavelength optimized for platinum-cobalt (Pt–Co) color scale measurement—commonly expressed in Platinum-Cobalt Units (PCU). Unlike subjective visual comparison methods, the GDYS-101SB employs a stable LED light source, precision optical filters, and a calibrated silicon photodetector to convert transmitted light intensity into a digital PCU reading. Its design prioritizes operational robustness in non-laboratory environments, including water treatment plants, environmental monitoring stations, municipal inspection units, and field-based public health assessments. The instrument does not require external calibration standards during routine use, as its optical path and signal processing are factory-aligned to the Pt–Co reference curve defined in GB/T 5750.4–2006.

Key Features

• Compliance with GB/T 5750.4–2006: Fully aligned with the statutory methodology for drinking water color assessment in China, ensuring regulatory acceptability in official reporting.
• Field-Optimized Portability: Compact housing (approx. 180 × 85 × 55 mm), integrated rechargeable battery, and sealed optical chamber enable reliable operation under variable ambient lighting and temperature conditions (10–35 °C).
• Dedicated PCU Quantification: Measures across 0–200 PCU with a detection limit of 5 PCU—sufficient to resolve low-level discoloration associated with humic substances, iron/manganese dissolution, or industrial dye leakage.
• Fixed-Wavelength Photometry: Utilizes a narrow-band LED centered near 455 nm, matching the spectral sensitivity peak of the Pt–Co scale and minimizing interference from turbidity or background chromophores outside the visible blue region.
• Integrated Data Handling: On-device storage for up to 200 measurement records with timestamping; supports export via USB interface for traceability and QA/QC documentation.

Sample Compatibility & Compliance

The GDYS-101SB accepts standard 25 mL glass or quartz cuvettes (10 mm pathlength) and is validated for raw surface water, treated potable water, groundwater, and wastewater effluents meeting basic clarity requirements (turbidity < 5 NTU). Samples requiring pretreatment—such as centrifugation or membrane filtration to remove suspended solids—are processed per GB/T 5750.4–2006 Section 8.2. The instrument’s measurement uncertainty (±5%) is specified under controlled laboratory conditions at 25 °C and conforms to the repeatability criteria outlined in Clause 9.3 of the standard. While not certified to ISO/IEC 17025, its metrological traceability is established through factory verification against NIM (National Institute of Metrology, China)-certified Pt–Co reference solutions. It is intended for use in GLP-aligned environments where documented method adherence—not full GMP compliance—is required.

Software & Data Management

Data acquisition and review are managed via the built-in LCD interface with intuitive menu navigation. All measurements include automatic zeroing using a reagent blank (deionized water), and user-initiated calibration checks can be performed using supplied 10 PCU and 100 PCU reference standards. Exported data files (.csv format) contain sample ID, measured PCU value, date/time stamp, operator code (if entered), and instrument serial number—supporting audit readiness for internal quality reviews. No proprietary software installation is required; exported files are compatible with common spreadsheet and LIMS platforms. The firmware includes an event log that records power cycles, calibration attempts, and error codes—enabling technical troubleshooting without remote diagnostics.

Applications

• Routine surveillance of finished drinking water at distribution points to verify compliance with China’s Hygienic Standard for Drinking Water (GB 5749–2022), which specifies ≤15 PCU for aesthetic acceptability.
• Source water characterization during flood events or algal bloom periods, where rapid color screening informs coagulant dosing adjustments in conventional treatment trains.
• Effluent monitoring for textile, dyeing, and pharmaceutical facilities subject to local discharge permits referencing color limits.
• Field validation of point-of-use (POU) filter performance, particularly for activated carbon systems targeting organic colorants.
• Training and capacity building in regional CDC laboratories and rural water safety programs where benchtop spectrophotometers are unavailable.

FAQ

Is the GDYS-101SB compliant with international color standards such as APHA or Hazen?
The instrument is designed exclusively for Pt–Co (PCU) quantification per GB/T 5750.4–2006. While PCU, APHA, and Hazen units are numerically equivalent under ideal conditions, it does not implement ASTM D1209 or ISO 7887 algorithms and should not be used for regulatory submissions requiring those standards.
Can it measure colored samples with high turbidity?
No. Turbidity above 5 NTU introduces significant scattering error. Users must pre-filter samples through a 0.45 µm membrane or centrifuge at 3000 rpm for 10 minutes prior to analysis, as stipulated in GB/T 5750.4–2006.
What maintenance is required?
Routine cleaning of the cuvette compartment and optical windows with lens-grade tissue and isopropyl alcohol; annual verification against certified reference standards is recommended for continued accuracy assurance.
Does it support multi-wavelength analysis?
No. It is a single-wavelength photometer optimized for the 455 nm band. It does not provide spectral scanning or CIE color space conversion (e.g., CIELab).
Is firmware upgrade available?
Firmware updates are distributed directly by Jilin University–Xiaotianshe upon request and require USB connection and Windows-based utility software provided under license agreement.