ROTRONIC MBW 473 - Manual (Page 26)

22 MBW473_MANUAL_E_V2.0
Mirror Cleaning
Activating the Mirror Cleaning function with the respective key at the bottom of the screen will heat the
mirror to a pre-specified temperature, getting the measuring head ready for the removal of the cover
and the optical assembly. If the mirror and other internal measuring head components are disassem-
bled while they are cold and become exposed to normal atmospheric air, the possibility of undesired
condensation exists. Warming the mirror and other internal components to a safe head removal tem-
perature, greater than or equal to the current ambient temperature, will prevent the formation of dew
on the mirror assembly during servicing.
To set the Minimum Mirror Temperature when activating the Mirror Cleaning mode:
1. Select the Control Setup menu by
pressing the dark gray menu selection
key until Control Setup appears.
2. Touch the Mirror Cleaning menu button.
3. Touch the Change To: field to the right
of the Minimum Mirror Temp label.
4. Enter the temperature in degrees C which the mirror must warm to during the Mirror Cleaning
mode,. It is recommended that you enter your current ambient temperature or higher.
5. 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.
6. Press the OK button in the dialog box or press Enter on the keyboard to confirm the new value.
Press Cancel to leave it unchanged.
Mirror Check
Mirror Check is the process of warming the mirror to evaporate all condensation, looking for the pres-
ence of contamination and accounting for it if necessary, then initiating a new dew or frost point meas-
urement. Mirror Check may be started manually with the fixed Mirror Check key, or if enabled, it will
start automatically at pre-specified time intervals.
During a mirror check, whether triggered automatically or manually, the indicator on the fixed Mirror
Check key has the following meanings:
Red: The mirror is heating.
Brown: The mirror is holding at the programmed Mirror Check Temperature.
Yellow: The mirror is cooling to re-form the dew or frost layer.
Gray: The mirror check function is not currently active.
Once the system has re-established a dew or frost layer and become stable, the mirror check function
is completed and the color indicator turns gray.
After the Mirror Check is completed the bar of the Mirror Residue Indicator shows the amount of con-
tamination on the mirror. If the bar covers more than a quarter of the space, we recommend that you
clean the mirror. For instructions on mirror cleaning, please refer to section 7.3
’Mirror Cleaning’.