Kipp & Zonen BREWER MK IV Instruction Manual Download

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16-10-200716-10-2007

MKIV OPERATOR’S MANUAL

      866              4           16883           8442        869.5
      876              5           27775          12421        879.5
      887              7           40973          15486        891.5
      897              6           55779          22772        901.6
      908             10           71077          22477        911.6
      918              9           86191          28730        923.6
      929              8           99579          35206        933.6
      939             17          111900          27140        943.7
      950              9          122532          40844        955.7
      960             11          131484          39644        965.7
      971             14          138978          37143        975.7
      981             18          144932          34161        985.7
      992             17          149962          36371        995.8
     1002             15          153943          39748       1007.8
     1013             18          157825          37200       1017.8
     1023             19          160926          36919       1027.8
     1034             19          163407          37488       1037.9
     1044             22          165796          35348       1049.9
     1055             19          168082          38561       1059.9
     1065             24          170292          34761       1069.9
     1076             25          172626          34525       1082.0
     1086             26          175036          34327       1092.0
     1097             29          177199          32905       1102.0

A plot of the dark count and wavelength 1 intensity values vs the high voltage should be
compared to the plot in the Final Test Record.

The wavelength 1 data should exhibit a region of minimum slope (plateau).
The optimum setting for the high voltage is at the beginning of the plateau. The ratio is
determined by deviding the counts of wavelength 1 by the square root of the dark count.

If the new established optimum high voltage value deviates approximately 50 Volts or more
from the orignial setting then it is desired to change the current setting. See the HVSET
explanation on how to adjust the high voltage.

WARNING:

Changing the high voltage for the photomuliplier may effect the ozon
calibration, but will change the UV calibration for sure. The best time for
adjusting the high voltage is therefore during re-calibration of the Brewer
instrument.

HVSET: Set PMT High Voltage

HVSET is used to set the PMT High Voltage as determined from the HV test.
This test requires access to the High voltage module and the front of the Main Electronics Circuit
Board.
Prior to starting the test, locate shorting plug J2 and potentiometer R4 on the High Voltage Module,
and test point E16 on the Main Electronics Board.

Method

1. If not already done so, then turn off Brewer power and on the high voltage module move jumper

J2 from Pins 2-3 to Pins 1-2, and restore Brewer power.

2. Enter the

HVSET

command and enter the desired HV value at the prompt.

3. Measure the voltage at E16 on the Main Electronics PCB and write the value down.
4. Turn off Brewer power and set jumper J2 back to pins 2-3, and restore power.

5. Monitor E16 and adjust R4 on the High Voltage Module until E16 is set to the voltage as recorded

in step 3.

6. Confirm the setting with an AP command.

APPENDIX F FACTORY TESTS