MBW 473-RP2, Operation And Maintenance Manual

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30 MBW 473 Manual English V5.0
5.4 Control Setup
Using the Control Setup menu enables you to control the manner in which the 473 operates.
Dew / Frost Control
When measuring dew/frost points between 0 °C and -
20 °C, condensation on the instrument’s chilled
mirror may be in the form of dew, frost, or a combination of both. If the state of the condensation is
not known, it will introduce errors into all the humidity measurements reported by the instrument.
To eliminate this potential source of error, the Force Frost function is used to rapidly cool the mirror to
below -20 °C, forcing all dew on the mirror into frost. The mirror will then re-stabilize at the frost point
temperature. Once the condensate layer is in a state of frost, it will remain frost for all sub-zero mirror
temperatures, allowing the instrument to measure the frost point accurately. The dew point and all
other humidity measurements are then mathematically calculated from the frost point.
To change the Force Frost settings:
1. Select the Control Setup menu by
pressing the dark gray menu selection
key until
Control Setup appears.
2. Touch the Dew/Frost Control button.
The Mirror Dew/Frost Control window
will open.
3. The Force Frost function can be enabled or disabled by clicking on the Force Frost Below button.
If the indicator on the left side of the button is green, Force Frost is enabled. If the indicator is
grey, Force Frost is disabled.
4. To adjust the temperature below which Force Frost activates, click on the Change To : field to the
right of the Force Frost Below button. The field will turn white.
5. Enter the temperature in degrees C below which Force Frost should activate.
6. If you make an entry error, touch the field that holds the number you wish to change. Each time
you touch the field, the last digit entered will be deleted.
Press the OK button in the dialog box or press Enter on the keypad to confirm the new value. Press
Cancel to leave it unchanged.