ALTANA LCM plus - Manual (Page 9)

BYK-Gardner GmbH LCM plus 235 017 133 DE 0302
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C Colour Measurement
Whenever the instrument is turned on, a zero measurement is made, taking the empty value (i.e.
the pure transmission values without cuvette inserted) of the optical beam path and comparing it
with the empty value obtained in the previous zero measurement. If the difference between both
empty values is near zero, you can start measuring without calibration. Calibration is only required
in case of considerable deviations of the empty value due to e.g. fluctuations of temperature. The
calibration remains valid until the next recalibration. LCM plus features a calibration memory for
both path lengths employed (50mm square cuvette and 11mm round cuvette). If you have to use
two different path lengths, owing to the nature of your samples (e.g. bright samples with Hazen
values below 50 or strongly coloured samples with greater Gardner values), it is possible to
calibrate both path lengths and then toggle between them. LCM plus uses the corresponding set
of calibration data automatically.
C1 Calibration
LCM plus features a calibration memory for 11mm Dr. Lange round cuvettes and 50mm square
cuvettes. To be on the safe side, calibrate LCM plus at least every day. In the calibration, the
employed medium is assigned a transmission of 100% over the whole spectral range. Observe
the following rules for calibration:
•
The cuvette type selected for calibration must be identical to the one used for
measurement, otherwise wrong Iodine, Hazen and Gardner values are given.
•
Use always clean cuvettes and fresh distilled water for calibration.
Instrument calibration for colour measurement
2. Turn-on instrument and printer, if desired. After self-check
and zero measurement, LCM plus might ask for calibration.
If LCM plus is already on, make sure the cuvette
compartment is empty and press the blue CAL - key. The
display reads:
2. Fill a clean cuvette (material and path length to suit your
samples) with distilled water and put it into the measuring
compartment.
4. LCM plus detects the cuvette type automatically.
4. Now press the blue CAL - key again to trigger calibration.
5. When the calibration is over and the printer is on, date, time and selected cuvette type are
printed, e.g. :
Zero meas.m.
Please wait
Pleas ins. cuv.
for calibration
Calibration
Please wait