3. GENERAL OPERATION
Page 79
© 1998-2008 DH Instruments, a Fluke Company
When PG7601 is operating in absolute by vacuum mode using the internal vacuum sensor to
measure reference vacuum, automatic motorized piston rotation will not engage until the
reference vacuum value is within the
Ready
limit (see Section 3.4.3).
Most PG7000 platforms produced before 2006 use a solenoid based rotation actuation
system. The system is protected against overloading. If the duty cycle becomes excessive,
motorized rotation cuts OFF and remains off for a 25 second delay. During the cutoff time, [
]
has no effect.
3.9.8.1
<2PRE-DECEL>
PURPOSE
To turn ON and OFF a function that causes the automated rotation system to
begin the piston rotation deceleration when
[ENTER/SET P]
is pressed rather
than at the time mass is to be loaded.
On a PG7000 Platform equipped with motorized rotation, when AutoRotate is on,
the piston rotation deceleration function is used to stop rotation before masses
are loaded or pressure is adjusted. As the deceleration function can take up to
one minute to execute, it can be initiated the moment that
[ENTER/SET P]
is
pressed to enter a new pressure or mass target. The deceleration function then
runs while the new target value is being entered. However, when the next target
does not require changing main masses, it may not be necessary to stop piston
rotation. In these cases, the running the deceleration function is probably not
desired and it is not beneficial for piston deceleration to initiate it when
[ENTER/SET P]
is pressed. For this reason, the function to start piston
deceleration when
[ENTER/SET P]
is pressed can be turned ON and OFF.
If pre-deceleration is ON and AutoRotate is ON, piston rotation deceleration
always initiates immediately when
[ENTER/SET P]
is pressed.
If pre-deceleration is OFF and AutoRotate is ON, piston rotation deceleration
occurs after entry of the pressure or mass target value and only if the new target
requires changing main masses with a manual mass set or operation AMH if an
automated mass handling system is active.
OPERATION
To turn ON and OFF the function that causes stopping piston rotation to initiate
when
[ENTER/SET P]
is pressed, press
[ROTATE]
,
<2pre-decel>
. The cursor
is on the choice corresponding to the current state. Select
<2on>
for piston
rotation deceleration to initiate when
[ENTER/SET P]
is pressed. Select
<1off>
for deceleration to initiate only after entry of a new pressure or mass target and
only if main masses need to be moved or AMH automated mass handling needs
to be operated. The default is
<2on>
.
3.9.9
[GEN] (OPTIONAL)
PURPOSE
To turn ON and OFF automated pressure generation/control and view and edit automated
pressure control settings. Requires that an automated pressure generation/control
component be included in the PG7000 system and properly configured (see Section 2.4.9).
PRINCIPLE
PG7000s support automated pressure generation/control components. These components, when
properly configured and interfaced with the PG7000 platform, are controlled by the PG7000