Biochrom Libra Instruments

Biochrom Libra S2 Colorimeter

Biochrom Libra S2 Colorimeter


  • Single beam filter based colorimeter covering 440-680nm
  • Rugged, portable and easy to use
  • Extremely versatile and ideal for QC and educational applications.
  • Excellent value for money 
  • Rechargeable battery version available


The Libra S2 is a small, robust, easy to use instrument that has been designed with both the student and field user in mind. It is ideal for teaching principles of science and analysis in schools and colleges, as well as being rugged enough for measurements in hot or demanding environments such as QC measurements in industrial processes or remote location health clinics where simple diagnostic tests need to be made.

The samples can be measured in either standard or semi micro 10mm pathlength cuvettes or in 16mm diameter test tubes (adapters for 10/12 mm test tubes are available). The instrument surface is designed for ease of cleaning and decontamination. Rechargeable NiMH batteries are included in the Libra S2B and they will operate for almost a month on a single charge to provide complete portability.

The instrument measures in Absorbance and % Transmission mode as well as in simple kinetics, enabling changes in Absorbance over time and reaction rates to be determined (readings are taken approx. every second). It may be used to cover the 400 – 700 nm wavelength range as it has an integral, colour coded rotating wheel containing filters at 440, 470, 490, 520, 550, 580, 590 and 680nm. These are made from coloured gelatin and are encased in glass, so that the instrument can be used in “tropical” conditions. A filter is selected by moving the wheel until the required wavelength is displayed in the window above the cell compartment.

The instrument may be linked via a serial lead to either a serial printer for hardcopy output or to a PC for download of results to spreadsheet. It has an analogue output, and may also be connected to a chart recorder using a standard 2 x 4 mm socket to output absorbance-time data when in kinetics mode.

Ordering Information Order Code
Biochrom Libra S2 Colorimeter (mains only) 80-5000-02
Biochrom Libra S2B Colorimeter (mains /rechargeable battery) 80-5000-03
S2000P printer  (includes serial lead)  80-3000-94 
Spreadsheet interface software (requires serial cable) 80-2112-23
Serial cable 80-3001-00
Adaptor set for 10 and 12mm tubes 80-3000-57

Spare Parts
80-3000-58 Spare lamp
80-3000-59 Spare filter set
80-3001-25 2 rolls printer paper plus ribbon
80-2084-11 10mm pathlength, volume 2.5mL, polystyrene, pack of 100

Full Technical specifications are shown below. Optional accessories marked *

Technical Specifications
Specification Data
Type Visible 
Wavelength Range 440 - 680nm 
Wavelength Accuracy (+/-) 2nm 
Wavelength Reproducibility (+/-) 1nm 
Lamp Source Tungsten Halogen 
Beam Single Beam 
Optical System Gelatin Filters 
Bandwidth 40nm 
Detector Diode 
Photometric Range -0.3 to 1.99A 
Stray Light <1%T at filter wavelength 
Zero Stability n/a 
Baseline Flatness n/a 
Measurement Type Fixed Wavelength (Abs/%T), kinetics 
Cell Compatibility Cuvette 10mm 
Other Sample Containers Test Tube* (10, 12, 16mm) 
Cell Holder Single Cell 
Accessory Options Rechargeable Battery* (S2B) 
Method Storage n/a 
Compliance CE 
Data Output Print*, Export to PC* 
Display LCD 
Data Interface Serial 
Languages English, Manuals in French, German, Italian and Spanish 
Power Requirement 110-220V, 50/60Hz, 20VA 
Weight 0.6 Kg (1.2lb) 
Dimensions (WxDxH) 15 x 18 x 6cm (5.9 x 7.1 x 2.4 inches) 
Noise n/a 
Photometric Accuracy +/- 0.02A at 1A 
Photometric Reproducibility  
Spectral Scanning No 
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