Photomultiplier Tube (Pmt) Sensor Module - Teledyne T200 Operation Manual

Teledyne API – T200 NO/NO

12.7.12. PHOTOMULTIPLIER TUBE (PMT) SENSOR MODULE

12.7.12.1. OPTIC TEST
SAMPLE RANGE=500.0 PPB
TST> CAL
<TST
Continue pressing <TST or TST> until ...
SAMPLE PMT=2750 MV
<TST TST> CAL
SETUP X.X
PRIMARY SETUP MENU
CFG DAS RNGE PASS CLK
SETUP X.X
SECONDARY SETUP MENU
COMM VARS
DIAG
Note
06858E DCN7057
/NO Analyzer Operation Manual
2 X
The PMT detects the light emitted by the reaction of NO with ozone. It has a gain of
about 500000 to 1000000. It is not possible to test the detector outside of the instrument
in the field. The basic method to diagnose a PMT fault is to eliminate the other
components using ETEST, OTEST and specific tests for other sub-assemblies.
The optic test function tests the response of the PMT sensor by turning on an LED
located in the cooling block of the PMT (see Figure 12-9). The analyzer uses the light
emitted from the LED to test its photo-electronic subsystem, including the PMT and the
current to voltage converter on the pre-amplifier board.

To ensure that the analyzer measures only the light coming from the LED, the
analyzer should be supplied with zero air.

The optic test should produce a PMT signal of about 2000±1000 mV.
To activate the optics test, press:
NOX= XXXX
SETUP
NOX= XXXX
SETUP
EXIT
MORE
EXIT
While the OTEST is
active PMT should =
2000 mv ± 1000mv
This is a coarse test for functionality and not an accurate calibration tool. The
resulting PMT signal can vary significantly over time and also changes with low-
level calibration.
Concentration display
continuously cycles
through all gasses.
SETUP X.X
ENTER PASSWORD
8 1 8
DIAG
SIGNAL I/O
PREV
NEXT
Continue pressing NEXT until ...
DIAG
OPTIC TEST
PREV NEXT
SAMPLE PMT=2750 MV
<TST TST> CAL
Troubleshooting & Service
EXIT
ENTR
ENTR EXIT
EXIT
ENTR
NOX= XXXX
EXIT
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