DH Instruments E-DWT-H, Руководство по эксплуатации и обслуживанию

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3. OPERATION
Page 25 © 2009 DH Instruments, a Fluke Company
3.5.1 Filling And Priming, Reservoir Pump
It is important to remove air from the test system by filling and priming it before using the
variable volume to generate pressure. Failure to fill and prime will result in the need to use
multiple variable volume strokes to generate pressure.
The reservoir filling and priming pump is designed to push oil through the E-DWT-H and out
the TEST port into the test system. It can also be used to generate an initial pressure, saving
variable volume stroke.
To fill and prime the test system, prior to generating pressure with the variable volume,
proceed as follows:
See Figure 11 and Figure 12 for a dual Q-RPT or Figure 1 and Figure 8 for a single Q-RPT
E-DWT-H schematic and view when following this procedure.
Leave an open purge point (for example a loose fitting) at the highest point possible in
the test system that is connected to the E-DWT.
If not already open, open the TEST shut off valve to connect the E-DWT-H to the test
system.
Position the reservoir pump correctly by rotating the reservoir cap CW until the reservoir
vent valve is at the CLOSE position. Do not overtighten.
Be sure that the reservoir cap vent valve is open (loosened CCW).
Open the reservoir shut off valve to connect the reservoir to the test system.
Pull the reservoir priming pump knob up slowly to fill it with oil from the reservoir. Then
push the knob down firmly with moderate speed to seal the tip of the pump against the
reservoir seat and inject oil into the E-DWT-H and out the TEST port.
Repeat while observing the open purge point in the test system. When only oil and no
air comes out of the purge point, close and tighten the purge point.
If desired, repeat to set an initial pressure with the reservoir pump.
Be sure the variable volume is already filled and in the start position (Section 3.5.2,
- ), and the reservoir shut off valve is open.
Press down on the pump knob but do not release your downward force when the pump
gets to end of stroke or becomes to difficult to push down. While maintaining the
downward force on the pump knob, close the reservoir shut off valve to capture the
priming pressure.
W
Caution
Do not attempt to generate greater than 700 kPa (100 psi) using the
reservoir priming pump.
Once the system is filled and primed, use the variable volume to generate pressure to the
desired pressure set point (see Section 3.5.2).
W
Caution
When the reservoir cap vent valve is closed, the reservoir is not connected
to atmosphere so opening the reservoir shut off valve and the test shut off
valve may not fully vent the DUT. To be sure the DUT is fully vented to
atmosphere, OPEN the reservoir cap shut off valve and/or disconnect at
the TEST port.