Teledyne 9110EH - Nitrogen Oxides Analyzer - Manual (Page 88)

Operating Instructions Model 9110EH Instruction Manual
6.7.5. Optic Test
The optic test function tests the response of the PMT sensor by turning on an LED located in
the cooling block of the PMT (Fig. 10-15). 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 make sure 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 electrical test press
the following key sequence.
SAMPLE RANGE = 500.0 PPB NOX=X.X
< TST TST > CAL
SETUP
SETUP X.X PRIMARY SETUP MENU
CFG DAS RNGE PASS CLK MORE
EXIT
SETUP X.X SECONDARY SETUP MENU
COMM VARS DIAG
EXIT
DIAG SIGNAL I / O
PREV NEXT JUMP
ENTR EXIT
DIAG OPTIC RANGE = 500.0 PPB NOX=X.X
EXIT
SETUP X.X ENTER DIAG PASS: 818
8 1 8
ENTR EXIT
Press NEXT until…
DIAG OPTIC TEST
PREV NEXT
ENTR EXIT
Press TST until…
DIAG ELEC PMT = 2751 MV NOX=X.X
EXIT
While the optic test is
activated, PMT should be
2000 mV ± 1000 mV
NOTE
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.
6.7.6. Electrical Test
The electrical test function creates a current, which substitutes the PMT signal, and feeds it
into the preamplifier board. This signal is generated by circuitry on the pre-amplifier board
itself and tests the filtering and amplification functions of that assembly along with the A/D
converter on the motherboard. It does not test the PMT itself. The electrical test should
produce a PMT signal of about 2000 ±1000 mV.
74 M9110EH Rev 0