Fluke Calibration P3031, User Manual

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3-1
Chapter 3
Operation
Introduction
There is a monitor gauge fitted to the instrument top plate, to serve as a guide to the
operator by indicating the approximate pressure in the system.
1.
Ensure that both Inlet and Exhaust valves are closed.
2. Turn screw press out (counter-clockwise) to approximately half its travel.
3. Select the required weights and stack them on the piston assembly. The pressure
measured is the sum of the weights plus the piston/weight carrier.
4. SLOWLY open and close inlet valve until piston floats with the bottom face of the
lowest weight is level with the groove in the indicator post. This is the PCU mid-float
position, which is the height at which all internal corrections have been made with
reference to the pressure datum (top of the test port).
WEIGHT
gmg09.eps
Figure 3-1. Float Height Indicator Post
5. If the piston is over-pressurized (piston against top travel limit) then reduce pressure
by SLOWLY opening and closing exhaust valve until the piston floats freely. The
screw press can be used for fine control — turn in (clockwise) to increase, and out to
decrease pressure.