Source Module - Teledyne 6000B Operating Instructions Manual

1 Operational Theory

1.6.1 Source Module

Any one of three types of source modules may be used in your system.
The system model designation identifies the source lamp (see Figure 1 for a
list of codes).
The QI (Quartz-Iodine) and D 2 (Deuterium Arc) sources are mounted
in the source module which also contains the focusing lens.
The source power supply module provides power to the lamps. The
source power supply module houses the power supply, a connector for an
optional temperature controller to heat the sample cell, and an optional span
filter power supply.
The Quartz-Iodine lamp power supply is a switching regulator that
maintains a constant voltage (5 VDC) across the filament of the lamp. The
lamp is incandescent. Its envelope is filled with a halogen to avoid sputtering
of the filament, blackening the lamp envelope.
The D 2 lamp power supply is a combination current and voltage
regulator. It maintains a constant anode current in the D 2 lamp and controls
the voltage across the lamp's cathode (filament).
When power is turned on, relay K1 is activated and applies 10 VDC
across the filaments. After ionization of the Deuterium vapor, the lamp starts
to conduct from cathode (filament) to anode. This causes K1 to deactivate and
the filament voltage drops to 7 VDC, which is the operating voltage. The
voltage from anode to cathode which was 365 V before ionization, drops to
about 60 VDC after ignition. This is the operating voltage. A constant current
of 350 mADC is the anode current.
The Deuterium arc lamp is employed with samples whose component
of interest does not absorb at the high intensity peaks of the HG source
emission spectrum. The Deuterium arc produces a broadband of energy (200
to 400 nanometer) in the UV spectrum.
The HG (Mercury arc) source and its power supply reside in one
enclosure. A quartz lens focuses the energy into a beam for transmission.
WARNING: UNDER NO CIRCUMSTANCES SHOULD THE
SOURCE MODULE BE OPEN AND THE LAMP AL-
LOWED TO OPERATE UNLESS PERSONNEL IN
THE IMMEDIATE VICINITY ARE WEARING UV FIL-
TERING EYE GOGGLES.
1-8 Part II
Teledyne Analytical Instruments
Model 6000B