sewerin EX-TEC Combi, Руководство по эксплуатации

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24
3 Measuring operation
KZW - short-term value alarm
This monitoring mode is based on an averaging period, usu-
ally 15 minutes (cf. section 8.5: Setting the short-term value
interval).
The total concentrations of the pertinent
toxic gas over the averaging
period must not exceed the product of the MAK value and the
overshoot factor.
Gas MAK value Factor
carbon dioxide CO
2
0.50 vol.% 4
hydrogen sulphide H
2
S 10 ppm 1
carbon monoxide CO 30 ppm 2
Example: a constant reading > 2.00 vol.% (= 4 x 0.50 vol.%) over
15 minutes triggers the KZW alarm (main alarm) ,
which cannot be cleared.
KZW (Example: CO
2
)
the current short-term value
(e.g. 0.30 %VOL) since the
last time the instrument was
switched on is displayed
KZW appears in the LCD


pressing the arrow-up key
brings you to the next display
