Preparing The Calibration - wtw Turb 555 Operating Manual

Operation
Course of the
measurement
during calibration
38
If there are more possible calibration points between the
start and end of the calibration interval, they must be
used.
Always carry out the calibration in the sequence from the
highest to the lowest value.
Note
When you observe these rules, the instruments measures
with the accuracy specified in chapter 7 T
within the calibration interval.
A calibration standard is measured in several cycles. In
each measuring cycle, all four of the system detectors are
scanned one after the other.
For a precise calibration, a certain number of measuring cy-
cles per calibration standard is required. The number of the
remaining measuring cycles is displayed in the lower display
line. After the last measuring cycle the calibration step is fin-
ished.
For the 10 NTU and 100 NTU calibration standards, the cal-
ibration step is automatically repeated once.

4.4.3 Preparing the calibration

Perform the following preparatory activities when you want
to calibrate:
1 Switching on the measuring instrument.
2 Wait until the 30 minutes warm-up period is over.
3 Keep the calibration standards ready.
4 Make sure that the outsides of the cuvettes are clean,
dry, and free of fingerprints.
CAUTION
Never open the cuvettes with the calibration standards.
Turb 555 / Turb 555 IR
ECHNICAL DATA
ba41113e07 04/2009