Kipp & Zonen Brewer Mk III Operator's Manual page 49

TU Test UV Port Alignment
TU uses an external quartz-halogen lamp mounted over the UV dome to find the zenith
motor step position for which the radiation intensity is a maximum through slit #1 of the
spectrometer slit mask.
This is an alignment test and should be performed if alignment of the UV optics is suspect.
The results of the factory tests are found in the Final Test Record and are nominally 2112+/-
4 steps.
UM Umkehr Observations
UM results in data being collected which can be processed to produce an Ozone vs. Height
profile. Data is normally collected between solar zenith angles of 60 ° and 90° in the morning
and in the afternoon.
The zenith prism is pointed to a solar zenith angle of 0°, FW#1 is set to the 0 position, FW#2
is set to the 0 position, the iris is opened, and the Tracker is rotated CCW until it is
perpendicular to the sun. Intensity measurements are made at two sets of wavelengths -
long (320-330nm) and short (310-320nm), and continue until they are interrupted by the
operator, or by the next zenith angle in a schedule.
Raw data is put into the BJJJYY.nnn file, and is processed to a UJJJYY.nnn file by the SUM
command.
See also Appendix A and Appendix E.
UV Related Commands
There are a number of Brewer commands that are related to measurements taken through
the Ultra Violet (UV) Dome, and they are grouped together here for convenience. There are
typically two UV scan lengths - 'short' UVB scans, which cover the range from 290nm to
325nm, and 'extended' UV scans which cover the range 286.5nm to 363nm.
UA Timed UX scan
UA performs an Extended UV scan in 0.5nm increments and stores the data to a
UVJJJYY.nnn file. This is a 'timed' routine in that it starts on the next half hour after the
command is given.
On execution of the command, the prism is rotated to the UV dome, FW#2 is moved to the 1
position, FW#1 is moved to the 3 position, the iris is opened, and the tracker is pointed at the
sun.
See also Appendix A, and the UX command.
UB UV Summary for Schedules
Raw UV scan data is stored in a UVJJJYY.nnn data file. The UB scan instructs the program
to process and print the daily summary for UV measurements taken throughout the day.
Damaging Ultra-Violet values are calculated for each scan and written to a DUVJJJYY.nnn.
See also Appendix A.
UF Fast UVB scan
UF results in a UV scan being done in the ascending wavelength direction only.
The zenith prism is rotated to the UV dome, FW#2 is set to the 1 position, FW#1 is set to the
3 position, the iris is opened, and the tracker is pointed to the sun.
The UV spectrum is scanned in steps of 0.5nm, with and integration of 4 shutter cycles for
wavelengths less than 300nm, and an integration of 1 shutter cycle for wavelengths grater
than 300nm. All data is normalised to a 1 cycle observation and recorded in a UFJJJYY.nnn
data file. When scanning is complete, a calculation of the UVB/UVA McKinley - Diffey
weighted irradiance is computed and sent to the printer and written to the DUVJJJYY.nnn
data file.
See also Appendix A.
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MKIII OPERATOR'S MANUAL