Wireless Colorimeter and Turbidity Sensor

Product Code: PS-3215


The Wireless Colorimeter simultaneously measures the absorbance and transmittance of six different wavelengths. The sensor can be used to study Beer’s Law (absorbance vs. concentration), enzyme activity, photosynthesis, and the rates of chemical reactions (absorbance vs. time). After a simple calibration, students can quickly begin viewing live measurements as they materialize across the visible spectrum at 650 nm (red), 600 nm (orange), 570 nm (yellow), 550 nm (green), 500 nm (blue), and 450 nm (violet).

This sensor also functions as a high-quality turbidimeter for water quality analysis. Rather than simply measuring transmitted light, the Wireless Colorimeter and Turbidity Sensor measures light scattered at a 90 degree angle from the sample, resulting in accurate and repeatable measurements. Additionally, the internal housing for the cuvette is opaque, which limits ambient light interference to preserve accuracy.

When used with our ezSample snap vials for water quality testing, chemical concentrations can be determined using the built-in calibration curves for Ammonia, Nitrate, Phosphate, Chlorine and Iron. Values are reported in Parts Per Million (ppm) or grams per liter (g/L).  These chemical tests follow USGS protocols for determining these ions in the field.

How It Works

Absorbance and Transmittance: Light from a broad band white LED light source passes through the solution onto a CCD array which detects the light and analyzes it. Parts of the array are covered by narrow band filters which allow 6 of the visible wavelengths (Violet, blue, green, yellow, orange, and red) through to the detector. The absorption can be plotted as a function of concentrations to form Beer’s law plots or absorption over time graphed for kinetics investigations.  A collimated light source directed perpendicular to the sensor can be used for turbidity.

Important Note: Solutions used within this spectrometer should be compatible with polystyrene (cuvette material) and ABS (spectrometer housing material). Use a glass cuvette or 12mm test tube for solutions with strong organic solvents like acetone, which will damage the plastic cuvettes.

Lab Activities & Experiments


  • Beer’s Law (absorbance vs. concentration)
  • Measuring reaction rates using absorbance vs. time
  • Turbidity testing and colorimetric analysis in the field
  • Determining the concentration of an unknown solution
  • Comparing the turbidity of water samples


  • Stabilized light source for consistent readings
  • Measures six different wavelengths simultaneously
  • PASCO software displays the absorbance & transmittance at each wavelength in the appropriate color
  • Quick and easy calibration
  • Functions as both a colorimeter and turbidimeter
  • Wireless design enables data collection in the field

What’s Included


Cancer & Reproductive Harm.


Color detection/peak wavelengths
  • 650 nm (red)
  • 600 nm (orange)
  • 570 nm (yellow)
  • 550 nm (green)
  • 500 nm (blue)
  • 450 nm (violet)
Colorimeter Detector Ranges
  • ±25 nm from peak
Colorimeter Absorbance
  • 0-3 Abs units; useful range (0.05-1.5 Abs)
  • 0 – 100%
Colorimeter Precision
  • ± 0.03 Absorbance units
Turbidity Range
  • 0 – 400 NTU
Turbidity Accuracy
  • ± 5% NTU

Battery & Logging

Stored Data Points Memory (Logging) 1 >15,000
Battery – Connected (Data Collection Mode) 2 >80 hr
Battery – Logging (Data Logging Mode) 3 3 days
Battery Type LiPo

1 Minimum # of data points with all measurements enabled, actual results depend on enabled measurements.

2 Continuous use in a connected state until battery failure, actual results will depend on sample rate, active measurements, and battery condition.

3 Logging until battery failure, actual results will depend on sample rate, active measurements, and battery condition.

* Normal classroom use is the sensor in active use for 20min/lab for 120 lab periods/yr.

Replacement Parts

Cuvette Rack EC-3590
Cuvettes and Caps SE-8739
100 NTU Calibration Cuvette SC-3512
Micro USB Cable PS-3584

Also Available

Wireless Sensor Charging Station PS-3599
USB Bluetooth Adapter PS-3500
ezSample Snap Vial – Ammonia EZ-2334A
ezSample Snap Vial – Nitrate EZ-2333B
ezSample Snap Vial – Phosphate EZ-2337
ezSample Snap Vial – Iron EZ-2331

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