Koehler Instrument - Petroleum Colorimeter - Petrochemical Life Science Lab Instruments

The Single Scale Three-Field Petroleum Comparator is a precision instrument designed for accurate visual color grading of petroleum products in accordance with ASTM D1500 standards. It enables direct comparison between the test sample and calibrated colored glass filters housed in test discs that conform to specified chromaticity coordinates.

The comparator features a three-field viewing system, allowing the sample and two adjacent color standards to be observed simultaneously. This configuration simplifies the process of identifying the closest color match and improves grading accuracy. For applications requiring quick pass/fail assessment, the glass standards can be preset to defined upper and lower color limits, enabling rapid verification of whether the sample falls within acceptable tolerance levels.

Equipped with a tungsten halogen light source that is color-corrected to CIE Standard Illuminant C, the instrument ensures consistent and reliable lighting conditions independent of ambient light variations. A precision prism system aligns the three fields into a unified view, enhancing visual comparison and operator efficiency.

This comparator is ideal for laboratories, refineries, and quality control environments where consistent, repeatable, and standards-compliant color evaluation of petroleum products is essential.