2. INSTALLATION

2.4.2 CHECK PRESSURE MEASUREMENT OPERATION

2.4.2.1CHECKING ABSOLUTE MODE PRESSURE MEASUREMENT

If the RPM4 has an Axxx (absolute) Q-RPT, check that it operates properly in absolute mode.

Make sure that the TEST(+) port is vented to atmosphere.

Use the [RANGE] function key to select the Axxx (absolute) Q-RPT DF range (see Section 3.3.1).

Press the [MODE] function key and select <absolute> mode (see Section 3.3.3). Use [UNIT] to change the pressure unit if desired (see Section 3.3.2).

If SDS is CLOSED (<SDS CLOSED> flashes over the display of pressure on the top line of the display), OPEN SDS. Press [SDS], <2yes> to OPEN SDS (see Section 3.3.8).

Do NOT OPEN SDS with a pressure higher than the maximum pressure of the Q-RPT applied to the TEST(+) port. Damage to the Q-RPT may result.

Observe the current value of atmospheric pressure. Check that the value agrees with the local value of atmospheric pressure within measurement tolerances (see Section 1.2.2.1) Repeat this process for both Axxx (absolute) Q-RPTs if there are two in the RPM4. . If a Q-RPT does not agree within tolerance, it may need to be AutoZeroed (see Section 3.3.9), calibrated (see Section 5.2) or repaired.

2.4.2.2CHECKING GAUGE MODE PRESSURE MEASUREMENT

Make sure that the TEST(+) port is open to atmosphere.

Press the [MODE] function key and select <gauge> mode. Use [UNIT] to change the pressure unit if desired (see Section 3.3.2)..

If SDS is CLOSED (<SDS CLOSED> flashes over the display of pressure on the top line of the display), OPEN SDS. Press [SDS], <2yes> to OPEN SDS.

Do NOT OPEN SDS with a pressure higher than the maximum pressure of the Q-RPT applied to the TEST(+) port. Damage to the Q-RPT may result.

The value indicated should be near zero. It is normal for the Q-RPT to indicate a value other than zero when vented when gauge mode is first entered or the range is changed. Press [AutoZ]. This runs AutoZ to zero the Q-RPT reading (see Section 3.3.9.1). Upon return to the main run screen, observe that the indication of measured pressure has zeroed.

If the display fails to zero properly, RPM4 may need repair.

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© 2004-2007 DH Instruments, a Fluke Company

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Fluke RPM4 manual Check Pressure Measurement Operation, Checking Absolute Mode Pressure Measurement