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Operating Instructions - CPC3050
High-Speed Pressure Controller
CPC3050
8.7.2 Block and Bleed Valve (CPX-A-C4-8)
The block and bleed valve is used to purge the liquid from the device under test. It is a three-way valve
which blocks the instrument from being contaminated while bleeding the liquid out of the device under
test. An initial bleeding of the contaminants in the system can be done by the following procedure
• Before connecting the DUT to the system, remove as much liquid as possible from the DUT.
•
With the controller power off and both the block and bleed valve closed, connect the system as shown
below.
• Use the controller to apply a pressure close to the full scale pressure of the DUT.
•
Open the block valve slowly to pressurize the DUT. (note: the gas will flow in the direction of the con
-
troller to the DUT: high pressure to low pressure).
• After the system is pressurized close the block valve.
• Open the bleed valve and purge the system to atmospheric pressure. Observe the sump to see if any
liquid is purged.
• Close the bleed valve.
• Repeat steps 3 to 7 until no more liquid is observed coming out of the system.
• With the block and the bleed valves securely closed, vent the controller.
Figure 8.7.2 – Contamination prevention accessories
