Kipp & Zonen BREWER MK IV Instruction Manual Download

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16-10-200716-10-2007

MKIV OPERATOR’S MANUAL

Extended UV Wavelength Scan

UX causes the irradiance over the 286.5nm to 363nm range to be measured in 0.5nm
increments in ascending wavelength. The zenith prism is rotated to the UV dome, FW#2 is
set to the 1 position, FW#1 is set to the 0 position, the iris is opened, and the tracker is
pointed toward the sun. The UV spectrum is scanned, and the data is appended to a
UVJJJYY.nnn data file When scanning is complete, a calculation of the UVB / UVA McKinley-
Diffey weighted irradiance is computed, output to the printer and to the monitor screen, and
appended to the DUVJJJYY.nnn data file.
See also Appendix A.

W0-W4 Time delays

These five commands result in time delays of 1, 5, 10, 20, and 30 minutes respectively and
can be used in command strings or in schedules.

Extended External Lamp Scan

XL is a test command that results in an extended UV scan being performed with a Lamp
(rather than the sky) as the source of radiation.
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 rotated to the sun. The operator is asked for
lamp number and lamp-diffuser separation, and the radiation intensity is measured in 0.5nm
increments over the extended UV range. Data is sampled for 30 cycle time increments for
wavelengths less than 300nm and 20 cycle time increments for higher wavelengths.
Measurements are taken through slit #1 for wavelengths less then 350nm and through slit #5
for higher wavelengths.
Data is stored in an XLJJJYY.nnn file and is normalised to 1 cycle observations.
See also Appendix A.

ZB, ZC, ZS Zenith Sky Observations

ZB, ZC, and ZS are variations of the same command, and are used when sky conditions are
known and it is desirable to keep the observations separated.
ZB is usually used in clear sky conditions (Zenith Blue), ZC is used under cloudy conditions
(Zenith Cloud), and ZS is used when conditions are unknown (as is a schedule).
The zenith prism is pointed to a Zenith Angle of 0°, the iris is opened, FW#1 is set to position
0, FW#2 is set to position 2, and the azimuth tracker is pointed toward the sun.  FW#2 is
adjusted according to sky intensity.
Data is recorded on disk and is printed as previously determined by PN, PD, and PF
commands.
A ZS observation consists of seven sets of 20 cycles of the slit mask (a measurement), each
cycle taking a reading for 2*0.14 seconds on each wavelength.  Intensity data for six
wavelengths, and the dark count, from the seven measurements is recorded. The Azimuth
and Zenith positions are updated after each measurement.  After each measurement O

and

SO2, or NO2 are

calculated, after the seventh measurement all data is processed, resulting

in a single summary set for the total observation.
As a safety feature to prevent damage to the detector, the measurement may terminates if,
as a result of varying cloud conditions, FW#2 has initially been set to a low attenuation value
and clouds suddenly move out of the field of view.
ZP initiates a variation of the ZS command in which the Azimuth Tracker is rotated to an
angle perpendicular to the sun.
A ZS measurement takes slightly more than five minutes to complete.
See Appendix A.

Zero Zenith Prism

ZE positions the zenith prism to its zero-step position, or ZA=180°. The zenith reference is
found, and the prism is then moved back a constant number of steps from the zero-step
position.

4. BREWER COMMANDS