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Teledyne 2120 - Trace Nitrogen in Argon Analyzer User Manual

Page 17

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Trace Nitrogen in Argon Analyzer

Introduction

The following list is keyed to Figure 1-3 and serves to identify and

briefly describe the function of various internal components of the
Model 2120 analyzer.

1. Card Cage for PCB's — Contains the amplifier board, 4-20

mA conversion board, test point jacks. The interface board is on
rear of cage.

2. PMT Cover —Shields the PMT for noise reduction and

protects it from atmospheric impurities.

3. Hamamatsu PMT Socket — The socket contains the high

voltage supply for the PMT, the resistor ladder for the intermediate
dynodes in the PMT, and a 1.22 VDC reference voltage generator.

4. Control Relay — Controls the high voltage transformer.

5. Digital Panel Meter—Displays the nitrogen content of the

sample stream in parts-per-million (ppm).

6. Sample Vent Port — 1/4-in (0 64-cm) Swagelok

compression

fitting marked VENT. Used to connect the sample outlet line to
the vent system.

7. Analytical Cell — Cell through which an argon sample stream

passes at flow rate.

8. Sample Input Port With Flow Control Orifice — 1/4-in

(0.64-cm) VCR fitting marked INPUT Used to connect the
sample inlet line to the analyzer. Sample flow is controlled by
an internal orifice at this input.

9. Power Entry Module — Main power on/off function,

connector for input power cable, and fuse holder for the
analyzer. Protects analyzer from input power surges and power
supply from shorts.

10. Optical Filter—Optically filters for wavelength of impurity

emission.

11. High Voltage Transformer — Supplies ionization voltage to

the analytical cell causing the sample gas to glow. The
transformer is powered by the AC line voltage.

12. Regulated 255-Hz Power Supply — A crystal-controlled

power supply with an adjustable output. The output is set to
supply a modulated 90 VAC output to the high voltage
transformer to ionize the sample gas in the analytical cell.

Teledyne

Analytical

Instruments

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