sewerin EX-TEC Combi, Руководство по эксплуатации

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5 Testing / maintenance
5.4 Testing the pump power, zero point and sensitivity
Proceed as follows:
screw the selected test gas can onto the test set SPE VOL as
far as it will go (fig. 1, item B)
connect the instrument‘s probe connection (item 3) with the
hose of the test set SPE VOL (fig. 1, item A)
switch the instrument on; the pump aspirates
fresh air through
the test set SPE VOL (fig. 1, item E)
enter your test results in the Inspection protocol
Pump power
use the needle valve (fig. 1, item F) to set the flow to maximum;
it must be greater than 30 l/h
Zero point
wait for the instrument to settle at a stable zero point; permis-
sible tolerances with fresh air are:
Gas Tolerance
Methane CH
4
-0.15 – +0.15 vol.%
(-3 – +3 %LEL)
Propane C
3
H
8
-0.06 – +0.06 vol.%
(-3 – +3 %LEL)
Nonane C
9
H
20
( ⊗ )
-0.05 – +0.05 vol.% or
(-3 – +3 %LEL)
Carbon dioxide CO
2
+0.04 – +0.10 vol.%
Hydrogen sulphide H
2
S -3 – +3 ppm
Carbon monoxide CO -3 – +3 ppm
Ammonia NH
3
( ⊗ ) -3 – +3 ppm
In a fresh air environment, the display of the oxygen sensor will
indicate a nominal value of 20.9 vol.%.
For zero calibration, the sensor is exposed to a pure CH
4
envi-
ronment (100 % by volume).
Tolerances
:
Oxygen O
2
-0.5 – +0.5 vol.%
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