Teledyne 9110T - Nitrogen Oxides Analyzer - Manual (Page 351)

Model 9110T NOx Analyzer Principles of Operation
Teledyne Analytical Instruments 351
Input
Ga
in S
elec
to
r 1
–
11
T
ype K
C
o
m
p
ens
at
ion
4
–
14
Ou
tpu
t S
ca
le S
ele
cto
r 2 –
1
2
Te
rmi
n
at
ion
S
e
le
ct
or
5
– 1
5
TC2
Not Used
TC1
T
y
p
e J C
o
mp
en
sa
tio
n
3 –
13
Purple Jumpers
Figure 13-19: Thermocouple Configuration Jumper (JP5) Pin-Outs
13.4. SENSOR MODULE, REACTION CELL
The 9110T sensor assembly consists of several subassemblies, each with different tasks:
 The Photo Multiplier Tube (PMT) detects the intensity of the light from the chemiluminescence
reaction between NO and O
3
in the reaction cell. It outputs a current signal that varies in relationship
with the amount of light in the reaction cell.
 The PMT Preamplifier PCA converts the current output by the PMT into a voltage and amplifies it to
a signal strong enough to be usable by the motherboard’s A  D converter.
 It also supplies the drive voltage and gain adjustment for the PMT’s High Voltage Power Supply
(HVPS)
 The Thermo-Electric Cooler (TEC) controls the temperature of the PMT to ensure the accuracy and
stability of the measurements.