Fluke Calibration RPM4, Operation And Maintenance Manual

Page: 57 / 150

3. OPERATION
Page 47
3.3.9.1 [AUTOZ] IN GAUGE AND NEGATIVE GAUGE MODE
 PURPOSE
To “rezero” the active Q-RPT in gauge measurement mode.
See Section 3.5.1,

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 <z> 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 3.5.1). If AutoZ
is OFF for the active Q-RPT, and measurement mode, <AutoZ is off >
is displayed when [AutoZ] is pressed.
Running AutoZ in or parallel mode (see Section 3.5.7.3) autozeros both the
Hi and Lo Q-RPTs simultaneously.
To run AutoZ in gauge measurement mode, set gauge or negative gauge as the
measurement mode (see Section 3.3.3) and press
[AutoZ] from the main run
screen. If the Q-RPT is a Gxxx or BGxxx type, the display is <Preparing to
AutoZ> for five seconds to allow time for the bypass valve between the TEST(+)
and TEST(-) sides of the Q-RPT to assure zero differential pressure and for the
pressure to stabilize (see Section 5.6, Figure 8). <Running gauge AutoZ> is
displayed briefly before returning to the main run screen.
Before running AutoZ in gauge mode, ensure that the pressure applied to
the Q-RPT is truly zero gauge (atmospheric pressure). If running AutoZ in
gauge mode results in a zero offset that RPM4 considers unusually large,
<Confirm 0 gauge P!> is displayed when AutoZ is pressed. Check that zero
gauge pressure is applied to the TEST(+) port and there is no differential
pressure across the TEST(+) and TEST(-) ports and press ENTER to
continue or ESCAPE to abort.
Allow the RPM4 to stabilize at atmospheric pressure and ambient
temperature for 1 to 2 minutes before running AutoZ in gauge mode.