MANUFACTURED IN THE UNITED KINGDOM Eclipse Refractometer General Models User Guide
Eclipse Refractometer User Guide (Eng) General Models B+S Code: 45-095 Issue 5B November 2010 Order Code 45-01 45-02 45-03 45-05 45-06 45-07 45-08 45-26 45-27 45-41 45-44 Range 0 – 15 °Brix 0 – 30 °Brix 0 – 50 °Brix 45 – 80 °Brix 72 – 95 °Brix 0 – 32 °Brix 28 – 65 °Brix 0 – 30% Starch 10 – 30% Water in Honey 1.33 – 1.42 Refractive Index 0 to -40°C Antifreeze Order Code 45-45 45-46 45-65 45-66 45-81 45-82 45-91 45-92 45-93 45-94 Range 30 to -40°F Antifreeze 0 – 60% Vol.
Applying the sample to the refractometer Lift the illuminator flap, drip the sample on to the prism then close the illuminator flap, alternatively use the dribble feature; drip sample into the top of the closed flap. Applying sample directly to the prism Appling sample using the dribble feature Optical glass is relatively soft and care should be taken not to scratch the prism surface. Do not use metal spatulas or glass rods to apply samples but instead use softer materials such as plastic.
Precautions to improve accuracy Make sure that the prism is cleaned and dried between each reading, using a little clean water at room temperature, and a soft cloth to dry. Make sure the scale of the instrument is in sharp focus before taking readings, adjust the eyepiece if necessary. Look at the quality of borderline obtained. Poor sharpness may indicate insufficient sample on prism, or temperature gradients across the prism, or that the prism was not properly cleaned and dried after the last reading.
Temperature Correction Table The corrections necessary to remove the effects of temperature on the °Brix (% Sucrose) scale are shown in the table below. Please note that the Alternative Method for calibrating the low range models, as mentioned earlier will effectively compensate for this correction factor. This table gives mass fraction corrections to refractometric tables for sucrose solutions at 589nm for temperature different from 20˚C. Taken from ICUMSA, Appendix 2, SPS-3 (1998) page 8. Temp.
% Water in Honey Temperature Correction for 45-27 Eclipse refractometer Refractive Index is temperature dependant. It is therefore necessary to make corrections for measurements taken at temperatures other than the reference temperature (20°C). For correcting measurements of “Water in Honey” the following table may be used. Note that the table shows two decimal places in order that the value may be rounded up or down accordingly.
°Brix to Refractive Index Conversion Table The table below can be used to convert °Brix readings taken from the instrument scale into refractive index. 0 Refractive Index at 589.3nm and 20.0°C 1.33299 30 Refractive Index at 589.3nm and 20.0°C 1.38115 60 Refractive Index at 589.3nm and 20.0°C 1.44193 1 1.33442 31 1.38296 61 1.44420 2 1.33586 32 1.38478 62 1.44650 3 1.33732 33 1.38661 63 1.44881 4 1.33879 34 1.38846 64 1.45113 5 1.34026 35 1.39032 65 1.45348 6 1.
Certificate of Conformity This Eclipse refractometer was calibrated and tested by Bellingham + Stanley and has been found to meet the published specifications for this instrument. For the refractometer to continue to operate within our specifications, it should be kept in clean condition and well maintained in accordance with the user guide. This certificate implies no responsibility by Bellingham + Stanley with regard to the accuracy of the instrument after the date of examination at Bellingham + Stanley.
