Furness controls FCO770, Руководство пользователя

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FCO770 Users Guide Issue 1 Page 89
Set a Known Leak.
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Having set up a leak tight test item, select the 'PRODUCT DATA' menu and set the
Fill time to not less than 30 seconds.
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Start the instrument and let it go into the fill condition.
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Set a leak using the Microcalibrator. Any leak will do, but it is preferable to use a leak
that is approximately the same as the fail level for the test component. Do not use
leaks of less than 20 digits of the leak range chosen, and preferably not less than 50
digits, otherwise the calibration will be inaccurate. Do not use large leaks on small
volumes that cause the pressure drop to exceed the full scale of the instrument in less
than the set test time. Make a note of the leak set. e.g. leak = 5.0 cc/min. or 60 cc/hr.
Calibrate the Instrument.
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When a known leak is set, reset the fill time to its original value.
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Run the test as normal, starting with the test item fully vented. At the end of the test a
flow reading should be displayed.
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Select the 'CALCULATE VOLUME' (On the FCO770, this can be found in the
Utilities menu – Extended Utilities menu) and press the ENTER button.
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Select the test that you wish to modify.
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Adjust the CAL. LEAK value to match the value of the external calibrator leak e.g.
5.0 cc/min.
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The DISPLAY value shows the leak reading that was recorded in the last test or zero
if a test was not completed. Change this if required to be the same as FCO770 leak
reading.
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Select OK and press ENTER . The volume of the test item, test pipe and jig is
calculated and displayed. You are asked to confirm that you want to save the new
volume to update the Test Data.
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It may be necessary to repeat this procedure to confirm the volume calculation if the
original estimate of the test volume was considerably in error or if greater accuracy is
required.
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If the Microcalibrator is to be removed from the test port in normal use, then volume
of the Microcalibrator calibrator and its connecting tubes should be subtracted from
the volume entered.