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THEORY OF OPERATION
Model 400E Ozone Analyzer
Instruction Manual
230
P/N 04316 Rev: B
UV Lamp Power Supply
DC
Regulator
Center
Tapped
Transformer
Rectifier
Error
Amplifier
D-to-A
Converter
I
2
C Bus
+15 VDC
Transformer
Controller
UV Lamp
.
Figure 10-6: Photometer UV Lamp Powe r Supply Block Diagram
UV Lamp Temperature Control
A thermistor and DC heater attached to the UV Lamp to maintain the Lamp at an
optimum operating temperature.
Sample Gas Temperature Sensor
A thermistor attached to the quartz tube for measuring sample gas temperature.
Photometer UV Detector
The vacuum diode, UV detector that converts UV light to a DC current.
UV Detector Preamplifier
A preamplifier assembly, which convert the Detector’s current output into a DC
Voltage than amplifies it to a level readable by the Auto D Converter circuitry of the
instrument’s mother board.