Teledyne 514 Instruction Manual page 56

5.0 Maintenance & Troubleshooting
With the explosion proof units, the power module ZERO, REF, and
MEAS levels, and the control unit meter readout for component of interest
concentration all are read on the local meter.
1. Set the power module control functions as follows: NORM/REF
to REF, NORM/MEAS to NORM and NORM/ZERO to
NORM. The REF level is now displayed on the local meter.
2. Adjust the meter trimpot until the meter reads 90% of full scale.
The meter trimpot or the chopper stabilized log amp (C-14586)
and the log ratio board (C-14907) is R36, and on the adjustable
log ratio board (C-14907) it is R26.
3. Now switch the NORM/REF to NORM and NORM/MEAS to
MEAS. Meter should now read 9 volts if the PLD balance
adjustments were properly done.
Log Ratio Amplifier Adjustments (dwg. C-14907):
When the log amplifier integrated circuit (A-1) is replaced on the log
ratio amplifier circuit card, it is necessary to re-adjust potentiometers R7 and
R9 in order to balance the circuit. To make the adjustments, the user must
have an extender card, a 100K resistor for connection between A1-2 and
A1-7 (across C5), and a high impedance voltmeter to measure the voltage
between A1-7 and connector pin 9. Proceed as follows:
1. Temporarily install a 100K resistor across A1-2 and A1-7 (across
C5)
2. Disconnect connector pin 9 from 9 VDC by lifting a connection
on the extender card. Connect pin 9 of printed circuit card to A1-
1 (signal common).
3. Adjust R7 until the voltage measured at A1-7 is zero.
4. Remove 100K resistor from A1-2 and A1-7.
5. Reconnect connector pin 9 to 9 VDC.
6. Using a high impedance voltmeter to measure voltages at pins 7
and 9 of the card extender, adjust R3 on the peak detector circuit
card until they are equal. With the reference and measuring
voltages equal and at approximately 9 volts, adjust R9 of the log
circuit card until the voltage at A1-10 is zero.
7. The log amplifier module (A-1) is now balanced..
8. The adjustment of R1 will be done during chemical calibration.
This adjustment allows fine adjustment on the gain of A2, so that
the output of A2 will be 0 to 0.4 VDC when zero and span fluids
are passed through the analyzer.
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Teledyne Analytical Instruments
A Business Unit of Teledyne Electronic Technologies