Fluke HPMS - Manual (Page 49)

3. OPERATION
Page 39 © 2007 DH Instruments, a Fluke Company
When a head correction is being applied, it is indicated by in the fourth character from
the right in the top line of the MAIN RUN screen (see Section 3.1.1). When the head correction is
zero, the is not shown.
The default head height unit is inches and the fluid species is Nitrogen (N
2
).To change units
of head height between inches and centimeters and to change the test fluid species, use
[SPECIAL], <3head> (see Section 3.5.3).
3.3.8 [SDS]
 PURPOSE
The SDS function is not used in RPM4 A70M/A20M-AF.
3.3.9 [A
UTO
Z]
 PURPOSE
To run the AutoZ function that rezeros the active Q-RPT between full calibrations.
See Section 3.5.1,  Principle for a full explanation of the AutoZ function.
 PRINCIPLE
Run AutoZ is the function by which the current Q-RPT reading is compared to a reference,
P
std,0
, at atmospheric pressure to determine a new value of P
offset
. The value of P
offset
is then
used by AutoZ to automatically correct the Q-RPT for possible changes in zero over time
(see Section 3.5.1,
 PRINCIPLE).
3.3.9.1 [AUTOZ] IN GAUGE MODE
 PURPOSE
To “rezero” the active Q-RPT in gauge measurement mode.
See Section 3.51,  Principle for a full explanation of the AutoZ function.
 OPERATION
For the AutoZ function key to run AutoZ, AutoZ must be turned ON for the
active range and measurement mode. AutoZ ON is indicated by to the left of the
Q-RPT designator on the first line of the main run screen. AutoZ ON and OFF is set
using [SPECIAL], <1AutoZ> (see Section 3.51). If AutoZ is OFF for the active Q-RPT,
and measurement mode, is displayed when [AutoZ] is pressed.
To run AutoZ in gauge measurement mode, use [MODE] to set gauge as the
measurement mode (see Section 3.3.3) and press [AutoZ] from the main run
screen. is displayed briefly before returning to the
main run screen.