DH Instruments E-DWT-H, Operation And Maintenance Manual

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3. OPERATION
Page 45 © 2009 DH Instruments, a Fluke Company
Note
•
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-E-DWT
considers unusually large, <Confirm 0 gauge P!> is displayed. Check
that zero gauge pressure is applied to the E-DWT-H TEST port, the
reservoir shut off valve is closed and the TEST shut off valve is open.
•
Allow the RPM4-E-DWT to stabilize at atmospheric pressure for 2 to 3
minutes before running AutoZ in gauge mode.
3.7.11 [ENT/AutoTest] (Run AutoTest)
 PURPOSE
To run the AutoTest function which automatically runs a calibration test sequence (Quick Test
or File Test).
Note
Run AutoTest is accessed by pressing [ENT] from the Rate, RPT or Clean
DISPLAY mode (see Section 3.7.7). In other DISPLAY modes, the function
of [ENT] is specific to the mode.
 PRINCIPLE
RPM4-E-DWT supports AutoTest automated sequences to assist in the testing or calibration
of analog gauges and other pressure sensitive devices.
The AutoTest function is intended to:
•
AutoRange the RPM4-E-DWT (see Section 3.7.5) to the range of the DUT being
tested with settings appropriate for the tolerance of the DUT.
•
Step the operator through a planned sequence of test pressure increments if desired.
•
Alert the operator to possible out of tolerance conditions at each test point.
•
Log test data in RPM4-E-DWT that can be viewed following the test.
There are two types of AutoTest: Quick AutoTest and File AutoTest.
•
Quick AutoTest: The DUT and test parameters are entered “on the fly” during the
initialization of the test, then the test is executed if desired. In Quick AutoTest tests,
the test points are defined in % of test FS pressure.
•
File AutoTest: The DUT and test parameters are stored in a file (see Section 3.8.5.2)
and retrieved when a DUT is to be tested. In File AutoTests, test points are defined
individually.
AutoTest operation is oriented towards running tests in which the pressure is set to the DUT
cardinal point indication and then the actual reference pressure present is read from the
RPM4-E-DWT.
AutoTest Settings and Calculations
The data required to initialize an AutoTest is either entered “on the fly” (Quick AutoTest) or
retrieved from a file (File AutoTest). The data items required are:
•
Pressure unit of measure.
•
DUT full scale in pressure unit of measure.
•
DUT tolerance in
±
% FS (full scale).
•
Test increment in % FS (Quick AutoTest) or number of test increments and the value of
each increment in the pressure unit of measure (File AutoTest).