Fluke A20M-AF Manual Do Utilizador

© 2007 DH Instruments, a Fluke Company 

Page 138 

The difference between a Q-RPT reading and the AutoZero reference at the time AutoZ 
is run.  Used by the AutoZ function when Auto Z is ON to compensate Q-RPT readings 
for changes in zero over time. 

AutoZero reference value.  Value indicated by the device against which the Q-RPT is 
zeroed by AutoZ. 

Pressure adder, used to offset a Q-RPT or barometer to calibrate it. 

Pressure multiplier, used to adjust span of a Q-RPT or barometer to calibrate it. 

Operating mode of RPM4s with two Q-RPTs in which both Q-RPTs are used to measure 
together in parallel and the indicated pressure is the average of their readings.  This 
creates a pseudo Q-RPT designated HL. 

The maximum pressure limit of a Q-RPT.  If the pressure measured by the Q-RPT 
exceeds Pmax!, an overpressure condition occurs. 

Pressure controller calibrator manufactured by DHI.  RPM4 can be used as an external 
reference device for a PPC3.  PPC3 automates RPM4 pressure control. 

The transducer used by RPM4 for low uncertainty pressure measurement.  May be 
designated as Hi, Lo or HL depending on its position and role in t he RPM4. 

Q-RPTs are designated by a leading A, G or BG (absolute, gauge or bi-directional 
gauge) followed by three numbers and a letter indicating the maximum range of the Q-
RPT in kPa (nnnK) or MPa (nnnM). 

A DISPLAY function in which the rate of change of pressure in pressure unit/second is 
displayed. 

Front panel LED indication of when the pressure measured by RPM4’s active Q-RPT is 
stable within the stability limit.  Leading character of the second line when the inactive 
Q-RPT is displayed on the second line in Q-RPT DISPLAY mode. 

Parallel measurement mode in which both Q-RPTs of an RPM4 with two Q-RPTs are 
used together and the indicated pressure is the average of their measurements. 

A system to protect Q-RPTs from overpressure made up of isolation and vent valves 
and internal operating logic.  SDS is not used in RPM4 A70M/A20M-AF. 

The difference between FS and the lowest point in a range.  For example, the span of a 
100 kPa FS range in negative gauge mode is nominally 200 kPa (from - 100 kPa to 100 kPa). 

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. 

The value from which deviations are measured in the Deviation DISPLAY function. 

A user settable maximum pressure limit.  When pressure exceeds UL, RPM4 beeps 
intermittently. In negative gauge measurement mode, there is also a user settable lower limit. 

Levels of security that can be set to protect certain RPM4 functions from being accessed. 

On-board automated test sequence that AutoRanges RPM4 based on characteristics of 
the Device Under Test (DUT).