Teledyne 8800A/8800B - Panel / Wall mount trace moisture analyzer - Manual (Page 30)

Section 3: Instrument
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• Make sure the instrument is unlocked.
• Press the MODE button a few times until the display shows CAL.
• Press the DOWN button to select the Self Calibration mode. The display will show SLF/CAL
• Press the DOWN button to confirm entry into the Self Calibration mode. The display will
show the reference dewpoint which has been previously programed into the instrument, the
SET and DEWPOINT legends will also appear. Use the UP and DOWN buttons to modify
this dewpoint to match the dewpoint of the known gas to which the sensor is exposed.
• Press the MODE button, the display will show BEG/S.C., prompting to begin the Self Calibra-
tion.
If the MODE button is pressed the calibration will be canceled and instrument will go to the
Serial Number mode. All setup will still be in effect, e.i. newly entered reference dewpoint
will remain in the instrument’s memory.
If the DOWN button is pressed the Self Calibration corrections will be disabled; any Self Cal-
ibrations performed previously will not be used in correcting the computed dewpoint of the
instrument.
• Press the UP button to initiate the Self Calibration. the display will show CNF/SC?, prompting
for a confirmation that the Self Calibration should be performed.
If the DOWN or Pressure Correct buttons are pressed the Self Calibration will be aborted.
• Press the UP button to confirm the Self Calibration. The display will show alternately S.C./
STB /-41.5
, indicating that Self Cal Stabilization is being checked and currently the instru-
ment is measuring -41.5°C. When the measured dewpoint is stable within 0.5°C for 3 minutes
the instrument will record the new single point self calibration values and finish by going to
the display dewpoint mode. Note that the program will spend atleast 3 minutes on this stage of
the calibration.
• The sensor may now be exposed to the sample gas and the instrument will display the mea-
surement using the newly acquired calibration values.
Scheduled Timer Activated Single Point Self Calibration procedure for instruments with
electrically actuated switchover valve and on-board battery backed real-time clock:
•
Make sure that your sample system is properly connected according to the sample system
instructions. When the timeouts and stabilization times are summed from the calibration
stages below, it can be determined that the calibration reference gas will be used for atleast 21
minutes, the user should make sure that there is sufficient amount of gas available. If the refer-
ence gas is provided from a compressed gas bottle, make sure that there is sufficient pressure
in the bottle, for some bottles there is a cut-off pressure below which the dewpoint is not guar-
anteed. Make a note of the exact dewpoint of the reference gas as it will be required in the next
steps.
• Refer to the unshaded area of the flow diagram on the second page of Appendix A.
• Make sure the instrument is unlocked.
• Press the MODE button a few times until the display shows CAL.
• Press the DOWN button to select the Self Calibration mode. The display will show SLF/CAL
• Press the DOWN button to confirm entry into the Self Calibration mode. The display will
show the reference dewpoint which has been previously programed into the instrument, the
SET and DEWPOINT legends will also appear. Use the UP and DOWN buttons to modify
this dewpoint to match the dewpoint of the reference gas.
• Press the MODE button, the display will alternately show 720 / HRS / INTR, indicating that