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5.0 Maintenance & Troubleshooting
Teledyne Analytical Instruments
A Business Unit of Teledyne Electronic Technologies
Photometric Laboratory Calibration
Procedure
1. Connect a recorder to the control unit.
2. Remove any screens placed over the sample cell that are in the
optical path.
3. Bolt cover on sample compartment.
4. Remove main cover from detector module to gain access to test
points.
5. Make certain proper optical filters are in place.
6. Small detector compartment covers must be in place.
7. Turn on analyzer and recorder.
8. With an oscilloscope, check all sync. pulses on the switch driver
and clamp circuit (refer to Table IV at the end of this chapter).
9. Wait one hour for warm-up.
10. Flow zero fluid into the sample cell. Lock in place. Zero fluid is
the background fluid with a minimum amount of the component
being measured.
11. With an oscilloscope, check the waveform at TP1 (violet).
Balance measure and reference peaks heights within 20%. The
clamped video should be between -0.4 to -2 volts P-P. The base
line is clamped to ground. Change the preamplifier gain resistor,
R4, to obtain -0.4 to -2 volts P-P, if necessary.
12. Connect one lead of a dual trace oscilloscope to TP2 (gray), the
other to TP3 (green).
13. On the peak level detector PCB connect a DMM to TP4 (orange)
and ground (any black test point). Adjust P2 on the automatic
gain control PCB until 9.00 volts are obtained.
14. With the meter at TP3 (yellow) adjust R3 on the PLD until the
calculated voltage is obtained. Some calculations will have to be
made to properly calibrate the analyzer when the zero fluid is not
exactly zero for the component of interest. When the zero fluid is
zero for the component of interest the PLD voltage at TP3 is set