HACH LICO620 Benchtop Colorimeter

Overview

The HACH LICO620 Benchtop Colorimeter is a precision optical measurement instrument engineered for reliable, repeatable color assessment of transparent liquids across industrial quality control, petrochemical refining, pharmaceutical excipient testing, and water treatment laboratories. It operates on the principle of spectrophotometric absorbance measurement using a dual-beam optical architecture—comprising a stable tungsten-halogen light source, interference-filtered photodetectors, and temperature-compensated electronics—to eliminate drift and ensure long-term calibration stability. Unlike subjective visual comparison methods, the LICO620 quantifies color by measuring absorbance at standardized wavelengths defined in internationally recognized protocols, converting optical density into traceable color units referenced to primary NIST-traceable liquid standards. Its design prioritizes metrological integrity over speed: each reading undergoes automatic zeroing, reference validation, and signal averaging to deliver high reproducibility (<0.3 APHA unit repeatability at low-range measurements). The instrument does not perform full-spectrum scanning; rather, it employs optimized fixed-wavelength detection aligned precisely with the spectral sensitivity profiles required by ISO and ASTM color scales.

Key Features

• Dual-beam optical system with real-time reference compensation to minimize lamp aging and ambient temperature effects
• Pre-programmed, factory-calibrated methods for five major international color standards: Hazen/APHA/Pt-Co (ISO 2211, ASTM D1209), Gardner (ASTM D1544), Iodine (ASTM D1500), Saybolt (ASTM D156), and ASTM D1500 petroleum color scale
• Integrated cuvette recognition logic that auto-selects pathlength (25 mm or 50 mm) and applies corresponding algorithmic correction factors
• Graphical LCD interface with multilingual support (English, German, French, Spanish, Chinese) and context-sensitive help prompts
• USB 2.0 interface compliant with CDC class drivers—enables direct connection to Windows/Linux systems without proprietary software installation
• Internal memory stores up to 1,000 measurement records with timestamp, operator ID, method name, and raw absorbance values
• Compliant with GLP data integrity requirements: all stored results include audit trail metadata (date/time, user login, calibration status, method version)

Sample Compatibility & Compliance

The LICO620 accepts standard square or rectangular glass or quartz cuvettes with nominal pathlengths of 25 mm or 50 mm. It supports aqueous solutions, hydrocarbon solvents, glycerin-based formulations, and clarified petroleum distillates—provided samples are optically clear (turbidity < 0.1 NTU) and free of suspended particulates. For ASTM D1500 and Saybolt applications, sample pre-filtration through a 0.8 µm membrane filter is recommended prior to analysis. The instrument meets the optical performance criteria specified in ISO/IEC 17025:2017 for colorimetric testing laboratories and conforms to the measurement uncertainty requirements outlined in EURACHEM/CITAC Guide CG4. All factory calibrations are traceable to NIST Standard Reference Materials (SRMs), including SRM 2200 (APHA color standards) and SRM 2210 (Gardner color standards). Routine verification can be performed using HACH’s certified liquid color standards kits (Cat. No. 2607700, 2607800), which include documented uncertainty budgets per ISO/IEC 17034.

Software & Data Management

Data export is supported via USB mass-storage mode: measurement files are saved in CSV format with UTF-8 encoding, containing columns for date/time, method ID, sample ID, measured color value, pathlength, absorbance at primary wavelength, and pass/fail flag against user-defined specification limits. The instrument does not require cloud connectivity or subscription-based platforms. For regulated environments, the LICO620 supports 21 CFR Part 11-compliant workflows when paired with HACH’s optional LabX® Lite software (v3.5+), enabling electronic signatures, role-based access control, and encrypted audit trail archiving. Raw absorbance data (A_λ) is retained alongside calculated color units, permitting retrospective reprocessing if updated conversion algorithms become available.

Applications

• Quality release testing of purified water (PW) and water-for-injection (WFI) per USP conductivity and color specifications
• Monitoring oxidation stability in transformer oils and turbine lubricants via ASTM D1500 trend analysis
• Batch-to-batch consistency verification of pharmaceutical intermediates, dyes, and synthetic resins
• Color grading of edible oils, biodiesel feedstocks, and hydrogenated fats per AOCS Cd 13b-92
• Validation of decolorization efficiency in activated carbon treatment systems for process water
• Regulatory submission support for FDA IND/NDA filings where color is a critical quality attribute (CQA)

FAQ

Does the LICO620 require annual recalibration by an accredited service provider?
No—routine user verification with certified standards is sufficient per ISO/IEC 17025. Full recalibration is recommended every 24 months or after physical shock, lamp replacement, or failure of verification checks.
Can the LICO620 measure samples with high viscosity, such as molasses or heavy fuel oil?
Not directly. Samples must be optically homogeneous and low-turbidity. Highly viscous or opaque materials require dilution or filtration per ASTM D5386 Annex A1 guidance.
Is method customization possible—for example, adding a custom color scale based on internal specifications?
No. The LICO620 implements only the five pre-validated, standards-compliant methods listed in its firmware. Custom algorithm development is not supported.
What is the warm-up time required before first use?
30 minutes at ambient temperature (20–25 °C) is recommended to stabilize thermal equilibrium in the optical bench and detector electronics.
How is traceability maintained during field use outside the primary lab?
Each instrument ships with a Certificate of Calibration showing NIST traceability, uncertainty budget, and measurement range. Portable verification standards (e.g., HACH 2607700 kit) enable on-site verification without sending the unit for service.