Fluke RPM4 manual Autoz in Gauge and Negative Gauge Mode

3. OPERATION

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.

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