DH Instruments PPC4, Руководство по эксплуатации и обслуживанию

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3. OPERATING PRINCIPLES
Page 41 © 2009 DH Instruments, a Fluke Company
3.2.22.1 Edit AutoZ

Caution
The edit AutoZ function should be used with great caution as
entering inappropriate values and turning ON AutoZ may result
in out of tolerance measurements. In normal day to day
operation, the value of the AutoZ offset, P
offset
, should be
changed using the run AutoZ function (see Section 5.7.5.1 for
Advanced Interface or Section 4.5.1.2 for Basic Interface) in
absolute measurement mode or automatically in gauge modes.
Before editing P
offset
, see Section 3.2.22.
Note
•
The value of P
offset
is always displayed and entered in
Pascal (Pa).
•
Edit and view AutoZ are not available for external Q-RPTs
in gauge mode.

OPERATION
For Basic Interface, see Section Section 4.5.1.1.
For Advanced Interface, see Section 7.2.7.2.
3.2.22.2 Run AutoZ
Note
•
Run AutoZ applies only to Axxx Q-RPTs in absolute
measurement mode. In gauge and negative gauge
measurement modes, AutoZ is run automatically whenever
the PPC4 is in the VENT condition.
•
Allow the PPC4 to stabilize at atmospheric pressure and
ambient temperature for 10 to 15 minutes before running
AutoZ.
•
While the value of P
std,0
is entered in the current pressure
unit of measure, the value of P
offset
is always in Pascal (Pa).
•
If running AutoZ results in a value of P
offset
that is greater
than ± 0.005 % FS of the span of the Q-RPT that is being
AutoZeroed, the Q-RPT and/or the reference used as the
source of Pstd,0 may be out of tolerance or the AutoZ
process may have been faulty. Before activating a new
P
offset
greater than ± 0.005 % FS of the active Q-RPT, check
to be sure that both the Q-RPT and the reference were in
good working order, properly vented to stable
atmospheric pressure, at the same height, and reading in
the same pressure units when AutoZ was run.
•
When running AutoZ, if a HEAD correction is currently
active (see Section 3.2.16), it is momentarily disabled to
avoid “zeroing out” the head value.

OPERATION
For Basic Interface, see Section Section 4.5.1.2.
For Advanced Interface, see Section 5.7.5.1.