3. OPERATION
Page 37
© 2009 DH Instruments, a Fluke Company
The ranges available on a PPCH system are accessed using
[RANGE]
(see Section 3.3.1)
and/or created using
[AutoRange]
(see Section 3.3.4). External Q-RPTs connected to the
PPCH (see Section 3.2.5) are initialized using
[RPT]
(see Section 3.3.5).
Table 7.
Settings and to what they are specific (range, measurement mode, Q-RPT, system)
SETTING
PURPOSE
SPECIFIC TO
SECTION
Unit
Set pressure unit of measure
Range
3.3.2
Mode
Set pressure measurement mode
(absolute, gauge)
Range
3.3.3
Resolution
Set pressure display resolution
Range
3.4.2
Jog
Set jog step size
Range
3.4.3
Control
Set pressure control mode and
parameters
Range
3.4.6
Upper Limit
Set upper limit alarm
Range and measurement mode
3.4.4
AutoZ
Run AutoZ, ON/OFF, set and view value
Range and measurement mode
3.5.1
Screen
Saver,
Sound,
Time, ID,
Level
Set system user preferences
System
3.5.5
Head
Set fluid head correction height, fluid, unit
of measure
System
3.3.7
3.5.3
Valve
Drivers
Set status of external valve drivers
System
3.4.7
Cal
Various Q-RPT and utility sensor
calibration functions
Q-RPT, utility sensor or barometer
3.5.8
3.2.7
FLUID RESERVOIR LOW LEVEL WARNING
If PPCH’s fluid reservoir is allowed to become empty, air may be drawn into the
hydropneumatic pump (see Figure 9) causing it to lose its prime. If this occurs, operation is
interrupted until the pump is reprimed using an on-board pump priming routine (see Section
5.10.1).
To prevent against allowing the reservoir to become empty, PPCH’s internal reservoir is
equipped with a float switch to provide a warning when the level is low. The warning system
is active when using the internal reservoir or the external reservoir if it is connected as
recommended in Section 2.3.6.2.
A low fluid level condition is indicated by:
•
Ten rapid beeps when the low level is first observed during operation or on power up.
•
Intermittent display of
<Reservoir level low>
on the bottom left of the MAIN RUN
screen.
By default, when a low level condition is determined, PPCH pressure generation capability is
stopped. This is to avoid running the PPCH internal hydropneumatic pump dry for extended
periods if the reservoir becomes empty without an operator present. It is also possible to set
the PPCH so that operation will not stop when a low level condition is determined (see
Section 3.5.7.3.2).
The status of the reservoir low level warning may also be viewed using
[SPECIAL]
,
<7internal>
,
<3pump>
,
<2level>
(see Section 3.5.7.3.2).
The status of the reservoir low level warning can be determined by remote command over
the IEEE-488 or RS232 interface (see Section 4.4.3).
