PG7000™ OPERATION AND MAINTENANCE MANUAL
© 1998-2008 DH Instruments, a Fluke Company
Page 88
The resolution with which the
pressure to mass
mode mass loading
instruction is given depends on the resolution set in the RES function. The RES
function makes it possible to avoid loading high resolution mass values when it is not
imperative that the pressure defined be exactly the nominal pressure requested (see
Section 3.9.10).
The
pressure to mass
loading instruction is given in nominal mass while the
main run screen displays the true mass loaded. For this reason, the nominal mass
loading instruction and the true mass displayed in the main run screen are slightly
different values. This is normal operation (see Section 3.6).
3.9.11.2
[ENTER/SET P] IN MASS TO PRESSURE MODE
PURPOSE
To enter and execute a
mass to pressure
command in
mass to pressure
mode
(see Section 3.9.12).
OPERATION
Put the PG7000 in
mass to pressure
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.
Edit field for total trim mass currently loaded.
2.
Edit field for nominal mass of main and
fractional masses currently loaded.
Load nominal mass:
10.0 kg and 3.17 g
Use the numerical and editing keys to enter the nominal mass to be loaded on
the piston following the mass loading protocol described in Section 3.6.
Press
[ENTER/SET P]
to process the mass value. If the mass value entered
cannot be executed, an explanatory error message is displayed momentarily and
operation returns to the mass entry screen with the previous nominal mass value
displayed. If the mass value entered is valid, the value is processed and
operation proceeds to the previous run screen with the new mass value active.
To make “in tolerance” measurements, it is imperative that the value of mass
loaded on the piston be the NOMINAL mass following the protocol describe in
Section 3.6. This ensures that PG7000 will correctly determine the true mass value
loaded. Failure to enter nominal mass values following the PG7000 mass loading
protocol is likely to result in out of tolerance mass load determination and pressure
definitions.