Teledyne 514 - NDIR analyzer - Manual (Page 67)

5–29
Maintenance & Troubleshooting 5.0
Teledyne Analytical Instruments
A Business Unit of Teledyne Electronic Technologies
adjust R16; decrease R17 if you run out of adjustment with R16.
The actual limit is 0.5 volts, with 0.4 volts giving some leeway.
The log circuit will give accurate results for much higher voltage
(as high as 4 volts), but the next stage (E-to-I) will not be
accurate above 0.5 volts in.
24. As a check go back to the zero fluid. The meter should read the
correct zero fluid concentration. Record the data points as in step
23.
25. Lock zero fluid in the sample cell. Run overnight stability.
Visually inspect the sample cell for bubbles, indicating sample
outgassing and cell leakage. Stability can also be run by
removing the liquid from the sample cell, and drying out the cell
with acetone followed by dry nitrogen or air purging. Screen the
optical path to obtain the same P-P voltages (as when liquid was
in the cell) at TP1 (violet) on the automatic gain control PCB.
Purge with dry gas continuously.
Reference Filter
Measuring Filter
White Enamel
Chopper Motor
Shaft
Screen
Balance Ring
Reference Filter
Measuring Filter
Rotated 180 Degrees
Figure 5-1. Filter Wheel - Exploded View