Ice test, 2 ice test – ROTRONIC MBW 473 User Manual
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MBW473_MANUAL_E_V2.0
7.2 Ice Test
The measuring accuracy can be checked with a simple, built-in test. The test may be performed at any
time, and is recommended whenever the results of your normal measurements do not correspond to
expectations, and you suspect that there may be an error with the instrument.
The mirror must be visible to perform the Ice Test. If you have an SH2 measuring head,
remove the measuring head cover prior to the Ice Test as described in section 7.3
’. If you have an RP2 measuring head, disassembly is not necessary as the mir-
ror is visible from the outside.
The Ice Test cannot be started as long as a dew/frost point measurement is in progress.
Make sure that the bar on the Dew/Frost Control key is grey.
Press the menu selection key on the lower right to select the
Units menu. Then press the Ice Test button.
Please note that the Ice Test will start immediately
after the Ice Test button has been pressed.
During the Ice Test, the mirror rapidly cools to approximately
-30 °C. Because the measuring head is open, humidity from
the ambient air starts to condense on the mirror. This forms
a frost layer on the mirror which can be facilitated if neces-
sary by blowing on it. After reaching the low temperature and
forming ice on its surface, the mirror begins to heat. As the
temperature approaches 0 °C, the instrument will beep in-
creasingly rapidly as the mirror gets closer to the ice-melting
temperature.
Watch the mirror closely. As soon as the mirror temperature
reaches 0 °C, the ice will melt into liquid water drops (phase
transition).