Teledyne 200A Instruction Manual page 147

Teledyne API Model 200A NO
Table 9-1: Test Functions (Continued)
Test Function
OZONE FL
PMT
NORM PMT
(table continued)
Analyzer Instruction Manual, 02246, Rev. F1
X
Factory Set-Up Comment
60 - 90 This is the Ozone flow. It is measured by a solid state flow meter,
and thus is a true indication of flow.
If you suspect there is no ozone being generated, disconnect the
tube at the reaction cell and rub the end of the tube on your
fingertips, then sniff your fingers. The odor of ozone should be
readily apparent.
This is the instantaneous output of the PMT. During normal
0-5000 mV
operation the value varies widely as the M200A switches from NO
to NO
synchronized with valve switching. The PMT voltage values will
be relatively constant when:
1. Electric test - variation in the 2000 mV signal observed will be
2. Optic test - variation in the 2000 mV signal will be PMT dark
3. Sampling zero gas - signal from 1, 2 plus signal from ozone
4. Sampling pure NO span gas - signal will be 1, 2, 3, above plus
1. Excessive background light which is caused by a possible
2. Humidity (undried ambient air) in the ozone generator feed air.
3. PMT recently exposed to room light. It takes 24-48 hours for
4. Light leak in reaction cell.
5. 5Improper slopes.
0-5000 mV The Normalized PMT reading is to be used as the PMT reading
during the FACTORY CALIBRATION procedure. In addition to
the raw mV reading from the PMT this reading is adjusted using
certain other factors to produce an accurate reading for the Factory
Calibration procedure.
to AutoZero modes. Changes in reading will be
x
sampling errors of the V/F board and preamp noise. See Section
9.1.3.2.
current, preamp, HVPS plus item 1 above. See Section 9.1.3.3.
generator air
signal from chemiluminescent reaction. Slight pulsations will
be noticed as the M200A switches from NO to NO
to differences in flowrates in each channel. These differences
are taken out in the calibration process resulting in slightly
different slopes for the NO and NO
when switching to the NO
converter.
When sampling zero gas the PMT reading should be less than
150 mV and relatively constant.
High or noisy readings could be due to:
contaminated reaction cell.
the PMT to adapt to dim light.
9-5
. This is due
x
channels. Large pulsations
x
channel is indicative of a bad moly
x