3. GENERAL OPERATION
Page 87
© 1998-2008 DH Instruments, a Fluke Company
OPERATION
Put the PG7000 in
pressure to mass
operation mode (see Section 3.9.12), then
press
[ENTER/SET P]
in any run screen. If automated rotation is on, the
<DECELERATING>
screen shows until piston deceleration is complete.
Pressing [ENTER] in the run screen causes automated pressure generation to
be suspended if ON (see Section 3.9.9) and AutoRotate to stop piston rotation if
ON (see Section 3.9.8). When [ENTER] is pressed to confirm mass entry,
automated pressure generation and/or motorized rotation resume.
The display is:
1.
Current measurement mode (see Section
3.9.4).
2.
Current pressure unit of measure (see Section
3.9.3).
3.
Entry field for the target value of pressure to
be set.
Target pressure:
100.0000 kPa a
Use the numerical keys and editing keys to enter the target pressure value desired.
Press
[ENTER/SET P]
to process the target pressure value. If the pressure
value entered cannot be executed, an explanatory error message is displayed
momentarily and operation returns to the target pressure entry screen with the
previous target pressure value displayed. If the target pressure value entered is
valid, the value is processed and operation proceeds to the mass loading
instruction screen. The display is:
1.
Mass to load using trim masses.
2.
Nominal mass to load using main and
fractional masses.
Load nominal mass:
10.0 kg and 3.17 g
If an AMH automated mass handling system is active and mass loading
resolution is set to 0.1 kg, the AMH loads the mass automatically. As it does, the
steps of its operation are displayed. If resolution is set to higher than 0.1 kg, the
operator is prompted to load the trim mass value.
With PG7601 in absolute by vacuum measurement mode (see Section 3.9.4), the instruction
is
<Load mass & vac:>
indicating that the nominal mass value should be loaded
and then the bell jar should be installed and vacuum established under the bell jar.
Load the nominal mass value following the protocol described in Section 3.6 and
press
[ENTER/SET P]
. When
[ENTER/SET P]
is pressed confirming that the
nominal mass value has been loaded, operation returns to the previous run
screen with the new pressure target and mass value active.
To make “in tolerance” measurements, it is imperative that all mass loading
instructions be executed following the protocol describe in Section 3.6. This ensures
that the actual mass value resulting from a nominal mass loading command will be
correct. Failure to load masses following the PG7000 mass loading protocol is likely
to result in out of tolerance mass load determinations and pressure definitions.
