Kipp&Zonen Brewer MkIII - Manual (Page 102)

MKIII OPERATOR’S MANUAL 99
RS: SLITMASK MOTOR RUN/STOP TEST
The RS test verifies that the slitmask motor (slitmask motor) is operating correctly.
In the normal, or "dynamic" mode of operation the slitmask is cycled rapidly, permitting individual
measurements to be made at intervals of 131 milliseconds. To ensure that the light intensities are
being properly measured in this dynamic mode, the RS test also measures intensities in a "static"
mode. Light passing through each slit is measured for a longer period of time during which the
slitmask motor is stationary.
Type RS. This test runs for approximately 10 minutes, including a five-minute warmup time for the
standard lamp. No further operator interaction is required. Results will be printed in a format similar
to the following:
Table F-3 Typical Slitmask Test Results
POSITION
0 1 2 3 4 5 6 7
RUN 234503 54 1760383 1681139 1704288 1529450 1313677 3062937
STOP 234100 55 1760880 1682069 1704610 1531027 1313654 3063356
RUN/STOP 1.0017 0.9818 0.9997 0.9994 0.9998 0.9990 1.0000 0.9999
RATIOS (RUN) -0.036 -0.0319 -0.0586 -0.99 0.2808 0.1657
RATIOS (STOP) -0.0346 -0.0306 -0.0564 -0.1005 0.2872 0.1682
The test is deemed successful if the ratio RUN/STOP for the five operational wavelengths (slitmask
positions 2..6) are in the range 0.997 to 1.003, and if the ratio for dark count (position 1) lies within
the range 0.20 to 5.0. If the ratios fall outside the acceptance range, there may be problems with
either the slitmask alignment, the slitmask-motor power supply or drive circuitry, or an improper
motor timing constant may have been stored in the instrument Constants File (refer back to the
slitmask-motor timing test, SH).
Normal operational ratios (R1 - R6) are printed out in the last two lines so that ratios in the dynamic
(RUN) and static (STOP) modes can be compared.
DT: PHOTOMULTIPLIER DEADTIME TEST
The DT test measures the deadtime of the photomultiplier and photon-counting circuitry. This test
takes readings at four slitmask positions:
Slitmask Position Description BASIC Variable
1 Darkcount F(1)
3 Wavelength 2 F(3)
5 Wavelength 4 F(5)
7 Wavelength 2&4 F(7)