DH Instruments PPC4, Operation And Maintenance Manual

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PPC4™ OPERATION AND MAINTENANCE MANUAL
© 2009 DH Instruments, a Fluke Company Page 160
PS
Purpose Set a new target pressure and start a new pressure generation cycle. Allows the test volume
to be specified which causes the pressure generation cycle to be executed omitting the
automated control configuration routine.
Command
“PS n (,v) ”
Classic “PS= n (,v) ”
Arguments n:
v:
The target pressure in the current pressure units.
The volume of the system connected to the PPC4 TEST(+) port in cm
3
(cc).
This argument is optional and should be used only to reduce pressure
setting time in know volumes.
Remarks The PPC4 sets the specified target pressure using the current control settings and mode.
Control continues until a new target pressure is set, the PPC4 goes into LOCAL mode, or an
“ABORT” program message is executed. If the given target is ‘0’ and the pressure units are
gauge, the PPC4 vents.
The “PR?”, “PRR?”, “STAT?”, or “SR?” program message queries can be used to monitor the
progress of the pressure setting routine.
If the optional “ v ” argument is used, the PPC4 does not perform its test volume determination
routine at the beginning of the pressure setting procedure, but instead uses the volume
specified for the pressure generation. This can reduce pressure set times when operating
into a consistent volume since the configuration routine takes 5 to 6 seconds to execute. The “v”
argument should only be used in automated conditions, where the test volume is constant
and the configuration does not change. This argument is only an approximation value, and it
may be adjusted empirically for correct operation. A higher “v” setting speeds up the
generation with a higher risk of significant control overshoot. A lower “v” setting slows down
the generation and reduces overshoot. Note: When using a BG15K or G15K low gauge
pressure Q-RPT with a DVU, the volume size specified should NOT include the DVU volume.
Example
(enhanced)
Cmd sent:
Reply:
“PS 1000”
“1000.000 kPa a “ (no reply if IEEE-488)
Example
(enhanced)
Cmd sent:
Reply:
“PS? 1000”
“1000.000 kPa a “
Example
(classic)
Sent:
Reply:
“PS=1000, 75” (includes test volume definintion)
“1000.000 kPa a “
Errors ERR# 6 The target pressure is out of range.
See Also “PR”, “PRR”, “STAT”, “SR”, “QPRR”
3.2.2, 3.2.12
PSF
Purpose Set a new target pressure, using only the fast control valve(s) and aborting pressure control
once the pressure target is reached..
Command “PSF n ”
Classic “PSF= n ”
Arguments N: The target pressure in the current pressure unit of measure.
Remarks The PPC4 sets the given target pressure using just the fast speed, and stops controlling
when the pressure has reached or passed the given target. The system does not attempt to
maintain the target pressure.
The “PR?”, “PRR?”, “STAT?”, or “SR?” program message queries can be used to monitor the
progress of the generation.
Example
(enhanced)
Cmd sent:
Reply:
“PSF 1000”
“1000.000 kPaa (no reply if IEEE-488)
Example
(classic)
Sent:
Reply:
“PSF=1000”
“1000.000 kPaa
Errors ERR# 6 The target pressure is out of range.
See Also “PR”, “PRR”, “STAT”, “SR”, “PSS”, “PS”
Figure 31