MPG2-H OPERATION AND MAINTENANCE MANUAL
© 2004-2008 DH Instruments, a Fluke Company
Page 10
During operation, if the VV runs out of stroke, the test shut off and reservoir shutoff valves
can be used in sequence to allow the variable volume to be refilled without releasing the
pressure on the TEST1 and TEST2 port (see Section 3.2.3).
The maximum operating pressure of the variable volume is 200 MPa (30 000 psi) with
MPG2-H and 100 MPa (15 000 psi) with MPG-H-HV and. Do not generate pressure greater than
the maximum operating pressure.
3.1.5
RESERVOIR
The reservoir is a 300 cc (18 in
3
) aluminum vessel mounted inside the MPG2 housing. It is
accessed for filling or cleaning by a screw on cover on the top surface of the MPG2 housing. The
reservoir is connected to the RESERVOIR ISOLATION valve by flexible tubing. The reservoir lid
can used to force fluid out of the reservoir into the system connected to the OPG1.
3.2
OPERATION
Operation of the MPG2 can be divided into three common tasks: filling and priming the system under test
(See Section 3.2.1); generating and adjusting pressure (see Section 3.2.2); filling or emptying the variable
volume while maintaining test system pressure (see Section 3.2.3).
3.2.1
FILLING AND PRIMING THE SYSTEM UNDER TEST,
PRIMING 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 pump is designed to push oil through the MPG2 and out the TEST port into the
test system. It can also 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:
Leave an open purge point (for example a loose fitting) at the highest point possible in
the system that is connected to the MPG2.
Open the reservoir shut off valve and the test shut off valve to connect the reservoir to
the rest of the system.
Position the reservoir cover correctly by rotating it CW until the reservoir vent valve is at
the CLOSE position. Do not over tighten; do not turn CW beyond CLOSE position.
Be sure that the reservoir cover vent valve is open (loosened CCW).
Pull the reservoir handle pump up slowly to fill it with oil from the reservoir. Then push
the handle down firmly with moderate speed to seal the tip of the pump against the
reservoir seat and inject oil into the MPG2 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 3.2.2, - ),
and the reservoir shut off valve is open.
