Fluke PG9000 Series, Руководство по эксплуатации и обслуживанию

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3. GENERAL OPERATION
Page 53 © 2011 Fluke Calibration
Note
•
The pressure unit of measure in which the range offered by the piston-
cylinder module using the active mass set is displayed can be changed by
pressing [UNIT] (see Section 3.10.3).
•
When the current pressure unit of measure is an altitude unit, piston-
cylinder module range is expressed in kPa if the altitude unit is meters (m)
or psi if the altitude unit is feet (ft).
3.10.3 [UNIT]

PURPOSE
To specify the unit of measure in which defined pressures are expressed.

PRINCIPLE
PG9000 supports a wide variety of pressure units of measure. Internally, PG9000 always
operates in Pascal [Pa] (the SI unit of pressure). Values of pressure are represented in other
units by the application of conversion factors to convert from Pascal. See Section 7.1.1 for
Unit of Measure Conversions.
The pressure unit of measure selection (e.g., psi, kPa, etc.) is separate from the pressure
measurement mode selection (gauge, absolute or differential). See Section 3.10.4 for
information on changing the measurement mode.

OPERATION
To change the pressure unit of measure, press the
[UNIT] function key from any run screen. The
display shows six place holders of units. If a desired
unit is not displayed, it can be added by the user.
1kPa 2Mpa 3Pa
4bar 5psi 6kcm2
The cursor is on the number corresponding to the active unit. To change the pressure unit, select
the desired unit. The display returns to the previous run screen with the selected unit active.
If the pressure unit selected is inWa (Inches of Water
column), the reference temperature for water density
must be specified. When inWa is selected as the unit,
the next display is:
Select inWa ref temp
4
°
C 20
°
C 60
°
F
Select the desired reference temperature for water density using the [
←
] or [
→
] key to move the
cursor. Pressing [ENT] returns to the main run screen with inWa based on water density at the
selected reference temperature as the active pressure unit. The current inWa reference temperature
can be viewed by observing the position of the cursor in the reference temperature screen.
Note
•
See Section 7.1.17.1.1 for tables of the pressure unit of measure
conversion factors used by PG9000.
•
The UNIT function provides rapid access to a choice of up to six units.
The choice of units can be customized from a wider selection by the user
(see Section 3.10.3.1). The default units are:
1kPa 2MPa 3Pa 4bar 5psi 6kcm2
•
To restore the default UNIT function settings, use the Unit Reset (see
Section 3.12.9.2).
•
Certain internal and/or metrological functions (e.g., vacuum reference
pressure) are always represented in Pascal [Pa], regardless of the active
pressure unit of measure.
•
When the current pressure unit of measure is an altitude unit, atmospheric
pressure in the AMBIENT run screen is expressed in kPa if the altitude unit
is meters (m) or psi if the altitude unit is feet (ft).