Teledyne 6000B - Photometric analyzer - Manual (Page 44)

3 Operation Model 6000
3-18 Part I
Teledyne Analytical Instruments
Generally, you have a good zero when Slope is less than 0.05 ppm/s for
about 30 seconds.
Once zero settling completes, the information is stored in the analyzer’s
memory, and the instrument automatically returns to the Analyze mode.
3.4.1.3 Cell Failure
Detector failure in the 6000B is usually associated with inability to zero the
instrument with a reasonable voltage differential between the reference and
measure voltages. If this should ever happen, the 6000B system alarm trips, and
the LCD displays a failure message.
Detector cannot be balanced
Check your zero gas
Before optical balancing:
a. Check your zero gas to make sure it is within specifications.
b. Check for leaks downstream from the Sample Cell, where con-
tamination may be leaking into the system.
c. Check flowmeter to ensure that the flow is no more than 200
SCCM
d. Check temperature controller board.
e. Check gas temperature.
f. Check the Sample Cell for dirty windows.
If none of the above, proceed to perform an optical balance as described in
section 5.
3.4.2 Span Cal
The Span button on the front panel is used to span calibrate the analyzer.
Span calibration can be performed in either the automatic or manual mode.
Make sure the span gas is flowing to the instrument.
3.4.2.1 Auto Mode Spanning
Observe all precautions in sections 3.4 and 3.4.2, above. Press Span to
enter the span function. The screen that appears allows you to select whether the
span calibration is to be performed automatically or manually. Use the
ΔΔΔΔΔ∇
arrow keys to toggle between AUTO and MAN span settling. Stop when AUTO
appears, blinking, on the display.