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Operating Manual Xenotest
®
220/220+
7
Operation
7.4 Setting the test chamber humidity
The desired humidity in the test chamber is entered as
a parameter on the instrument control panel. The maxi-
mum humidity which can actually be achieved in the test
chamber depends on the ambient conditions. In addition,
the amount of humidity which must be introduced into the
test chamber by the humidifier has an influence on the
maximum temperature which can be reached in the test
chamber. In dry ambient conditions, it may not be possible
to reach the maximum settable test chamber temperature
of 65 °C in the instrument.
Fig. 41:
The diagram shows maximum test chamber temperature
which can be achieved at the given test chamber humidity
under dry laboratory conditions, i.e. 20 °C and 30% r.H.
The irradiance was set to 42 W/m
2
(XENOCHROME 320)
or 48 W/m
2
(TM16 filter system).
7.5 Temperature fields
Fig. 42:
The diagram shows the ΔT temperature fields for XENO
-
CHROME 320 and TM16 filters depending on the irradi
-
ance. The black standard temperature (BST) is regulated
by the fan speed and dependent upon the irradiance, test
chamber temperature and the selected filter system. The
setting range for the fan speed is between 500 and 2,500
rpm. Minimum ΔT values are possible at maximum fan
speed and maximum ΔT values at minimum fan speed.
Fig. 42
depicts an ideal representation of the temperature
ranges based upon irradiance and filter type.
Fig. 41
Fig. 42
10
20
30
40
50
60
70
80
90
15
20
25
30
35
40
45
50
55
60
65
70
TM16, 48 W/m
2
XC320, 42 W/m
2
/°
C
Rel. Humidity/ %
Chamber temperature CHT
T=
-/
°C
Irradiance E
300-400
/ W/m
2
CHT
25
30
35
40
45
50
55
0
5
10
15
20
25
30
35
40
500 rpm
XC320
TM16
2500 U/min
B04
BST