Thermo Scientific 43i, Инструкция по эксплуатации

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Calibration
Zero/Span Check
4-10 Model 43i Trace Level-Enhanced Instruction Manual Thermo Fisher Scientific
15. Plot a graph of instrument readings against the SO
2
concentrations
generated for the high range.
16. Connect a source of calibration gas to the SAMPLE bulkhead. The
calibration gas should be approximately 80% of the low full-scale
range.
17. Use to move the cursor to Calibrate LO SO
2
, and press to
display the Calibrate LO SO
2
screen.
The first line of the display shows the current SO
2
reading. The second
line of the display is where you enter the low calibration gas
concentration.
18. To enter the low calibration gas concentration, use to
move the cursor left and right. Use to increment and
decrement the digit. Press to calibrate the instrument to the low
SO
2
calibration gas.
The display flashes the message “SAVING”, and the corrected SO
2
reading is displayed.
19. Press to return to the Calibration menu.
20. Generate five SO
2
concentrations equally spaced between zero and the
concentration above.
21. Record instrument reading for each concentration after allowing time
for both gas generation system and instrument to stabilize.
22. Plot a graph of instrument readings against the SO
2
concentrations
generated for the low range.
This is the instrument calibration curve. All future measurements
should be interpreted using this curve.
The zero/span check procedure is normally performed any time a quick
check of the accuracy of the instrument is required. Normally, zero and
span are checked daily. As experience is gained with the instrument, the
frequency of these checks can be adjusted accordingly.
The span gas concentration used in the span check should be between 70%
and 90% of the full-scale range. The zero and span drift should be
measured and recorded prior to making any adjustments.
Zero/Span Check