PPCH-G™ OPERATION AND MAINTENANCE MANUAL
© 2007 DH Instruments, a Fluke Company
Page 150
PM
Pressure multiplier, used to adjust span of a Q-RPT, utility sensor or barometer to calibrate it.
Q-RPT
(Reference Pressure
Transducer)
1. The transducer used by PPCH-G for low uncertainty pressure measurement. The Q-
RPT in a single Q-RPT PPCH-G, or the higher pressure range Q-RPT in a dual Q-
RPT PPCH-G, is referred to as the Hi Q-RPT.
2. The lower pressure range Q-RPT in a dual Q-RPT PPCH-G is referred to as the Lo Q-
RPT.
PPCH-G Q-RPTs are designated by a leading A (absolute) followed by three
numbers and a letter indicating the maximum range of the Q-RPT in MPa (nnnM).
Ramp Control Mode
Automated pressure control mode in which pressure is set and maintained at a target
rate of change
Rate
The rate of change of the current measured pressure. Indicated in the MAIN RUN
screen when control is suspended and in certain phases of automated pressure control.
Ready/Not Ready
Indication used to indicate when control PPCH-G pressure meets specific behavior
criteria.
Ready/Not Ready
is indicated by an LED on the PPCH-G front panel and is
used to determine when test readings should be taken.
RPM4
Reference Pressure Monitor manufactured by
DHI
. RPM4s can be set up to act as external
measurement devices to operate with PPCH-G.
Span
The difference between FS and the lowest point in a range.
Stability Limit
A limit expressed in units of pressure per second (e.g., kPa/second). The stability limit is
used as the
Ready/Not Ready
criterion.
Ready
if rate of change is less than stability limit.
Not Ready
if rate of change is greater than stability limit.
Static Control
Control mode in which the pressure is set near the target value and then shut OFF and
allowed to evolve freely.
Target Pressure
The value to which dynamic, static and monotonic automated pressure control sets the
pressure.
UL
Same as Upper Limit.
Upper Limit
A range specific maximum value of pressure not be exceeded and at which PPCH-G will
abort pressure setting and beep.
Utility Sensor
The internal, high (IuH) transducer in a PPCH-G if when there is no Q-RPT in the IH
position. A utility sensor is a low accuracy pressure transducer used for pressure
indication, safety and housekeeping functions, not for low uncertainty measurement.
User Level
Levels of security that can be set to protect certain PPCH-G functions from being accessed.
QDUT
On-board automated test sequence that AutoRanges PPCH-G based on characteristics
of the Device Under Test (DUT).
QTEST
Automated test sequence set up and executed using current PPCH-G settings.
X1H, X1L, X2H, X2L
External 1, Hi; External 1, Lo; External 2, Hi; External 2, Lo. Position designators of
Q-RPTs external to a PPCH-G (in RPM4s) that have been connected to PPCH-G and
initialized so that they can be used by PPCH-G for pressure measurement.
“1” is the first RPM4 in the communications daisy chain and “2” is the second.
“Hi” is the Q-RPT in the RPM4 if there is only one or the one that has the highest full
scale default range if there are two.
“Lo” is the lower of the two Q-RPTs if there are two Q-RPTs in the RPM4.
