wtw Turb 350 IR, Operating Manual, Page: 21 / 42

Operation
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4.3 Calibration
4.3.1 Basic information on calibration
Why calibrate? Just like any other measuring instrument, the measuring ac-
curacy of the Turb 350 IR has to be checked and adjusted
at regular intervals.
When to calibrate? Under normal conditions, we recommend calibrating the
measuring instrument at least every three months.
4.3.2 Calibration procedures
You have the following possibilities for calibrating the Turb
350 IR:
l
Four-point calibration over the entire measuring range ac-
cording to the specified calibration program (section
4.3.4).
l Partial calibration over a specified period of time (section
4.3.5).
l
Single-point calibration. This is a special user-defined cal-
ibration and only recommended as a temporary solution.
After a single-point calibration, measuring is only possible
close to the calibration point and with reduced accuracy.
Note
Calibrations with formazine are basically required for mea-
surements acc. to DIN/ISO or Standard Methods. For more
information, see Application report 998 255 P
RODUCTION OF
A FORMAZINE PRIMARY STANDARD
.