Xylem 600026, Руководство по эксплуатации

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Turb PLUS 2000 Setup , Configuration and Calibration
44 100193 Rev 0 ba77254e01 11/2020
6.3.2 Indexing Calibration Cuvettes
To achieve the greatest accuracy, and account for normal scratches and aberrations in cuvette
glass when calibrating, Xylem Analytics Germany recommends indexing the cuvettes.
Standards and standard kits purchased from Xylem Analytics Germany are supplied with indexing
rings. Complete instructions regarding how to index the cuvettes are included in the calibration
kits.
The following steps allow repeatable indexing of calibration standards:
1. With the instrument operating in AUTO mode insert the standard into the optical
well.
2. Slowly rotate the standard, inside the optical well, one complete revolution (360º).
While rotating the standard slowly, observe the measured turbidity and locate the
position of the cuvette having the lowest reading.
3. With the calibration standard positioned at the location having the lowest turbidity
reading, install the Indexing Ring over the cap on the standard so that the pointer
of the Indexing Ring faces directly forward.
When using the standards in the future, always insert the standard so that the pointer of the
indexing ring faces forward. Slowly rotate the standard back and forth about 5
° to find the lowest
point. The standard is now indexed and ready for use.
6.3.3 Calibration Procedures
NOTICE
It is recommended that the measurement chamber is kept covered during the
calibration period and that the flow through cuvette is replaced immediately after the
calibration to prevent premature saturation of the desiccant.
The 0-100 NTU range will be described below. If another range is selected
the Turb PLUS 2000 will prompt for appropriate standards during calibration.
1. Select the calibration function of the instrument by pressing the

button once. The arrow beside
CAL will be illuminated on the display. The lower display shows alternating 100 ( the value of the
standard that is requested) and

. The upper display shows the real-time reading to allow the
standard to be indexed. See section 6.3.2 for information on indexing cuvettes.
2. Remove the flow through unit.
3. Insert the requested 100 NTU standard. Index the standard to the lowest value on the upper display.