Xylem DR PORTABLE REFRACTOMETER - Manual (Page 2)

Basic Operation
Inserting the
battery Remove the four fixing screws from the cover plate on the underside of the
instrument. Fit the 9V battery type supplied. Do not allow moisture to enter
the battery compartment. Re-fit the cover plate before using the instrument.
Power On/Off Press the On/Off key to switch the instrument on. The temperature will then be
displayed in °C
To switch off the instrument, press the On/Off key. The instrument will
automatically switch off after a period of 90 seconds inactivity.
Cleaning the
prism It is important that the prism is completely clean before a test sample is applied.
Residues from sample remaining on the prism can dissolve in the applied sample
and affect the reading. Use a clean tissue and clean water (distilled or de-
ionised) to clean the prism and the prism dish. If oil samples are being
measured, then use ethyl alcohol additionally for cleaning. Do not use aggressive
solvents such as acetone.
Taking
readings Clean the prism carefully before applying the test sample. Apply enough sample
to cover the prism (0.4 ml is sufficient)
Press the Mes key. The reading will be displayed within 2 seconds
Take successive readings to check repeatability, allowing the sample to reach
prism temperature.
Temperature The prism temperature can be checked at any time by pressing the Temp key.
A second press of the Temp key will change the display from °C to °F, or vice
versa. Note, however, all measurements are automatically compensated to a
reference temperature of 20.0°C, irrespective of the actual prism temperature.
Changing the
scale Switch the instrument off.
Press and hold down both the Zero Set key and the Sample Read key and at the
same time press the On/Off key to switch the instrument on.
Instrument Calibration
To set or check the instrument calibration, use the Zero sample shown in the
Specification table overleaf. Zero Set & Check can be carried out on any scale.
‘0’ use distilled or de-ionised water
‘30’ use 30.00% w /
w
sucrose sample
‘60’ use 60.00% w /
w
sucrose sample
Zero set Clean the prism thoroughly and apply the Zero sample.
Press and hold down the blank Zero key until rEF is displayed (about 5
seconds). Within 10 seconds, press and hold down the Mes key until End is
displayed. This indicates the calibration (Zero Set) is complete.
Zero check With the Zero sample applied to a clean prism, press the Zero key. ‘zero check’
and the reading value will be displayed (with 0.01 resolution when using the
Brix scale). If the reading flashes, a Zero Set is required.
Certificate of Conformity
This Eclipse refractometer was tested and verified by Bellingham + Stanley Ltd. 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 a
clean condition and well maintained in accordance with this instruction sheet.
Bellingham + Stanley Ltd.
This certificate implies no responsibility by Bellingham + Stanley Ltd. with regard to the accuracy of the
instrument after the date of examination at Bellingham & Stanley Ltd
.
Checking/Validating the Instrument
Periodically, you may wish to check the performance of your DR refractometer. This may be
required as part of your Quality Management System. Suitable, certified calibration fluids for this purpose
can be obtained from Bellingham+Stanley Ltd.
Battery Low symbol
When this symbol is shown in the top left hand corner of the display, the battery should be
replaced. Fit a 9V battery type MN1604, 6LR61 or PP3. Ensure that a good quality battery is used and it is
inserted correctly. Do not allow moisture to enter the battery compartment. Re-fit the cover plate before
using the instrument.
Warning!
Always check the relevant Material Safety Data Sheet for a sample before applying it to the
refractometer. When applying samples that are harmful by skin or eye contact, wear appropriate
protective clothing and glasses. Avoid unnecessary contamination of the refractometer by confining
samples to the prism dish.
Caution!
The DR Digital Refractometer is a precision optical instrument and should be handled with care.
Do not drop or subject the instrument to sharp knocks. The instrument housing and display panel areas
are constructed from plastic materials that may suffer damage if contacted with aggressive organic
solvents. For example, avoid contact with solvents such as acetone and certain aromatic solvents. The
prism dish is chrome-plated, which could be corroded by certain acids and salts.
Maintain your DR Refractometer in a clean condition and avoid use and storage of the instrument outside
the specified temperature range. Avoid dusty and high humidity environments and prolonged exposure to
direct sunlight. Use the soft case provided to protect the instrument.
Deterioration/loss of the display may be indicative of low battery power or too low ambient temperature.
Do not persist in using the instrument with low battery power. Check/replace the batteries as necessary.
If “---“ is constantly displayed, contact B+S for advice.
If in doubt about the intended use of your DR, contact B+S for advice.