Fluke Calibration 4184297, Руководство пользователя

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3-1
Chapter 3
Operation
Introduction
All P3000 Series pneumatic deadweight testers have 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.
Single PCU Models — Pressure
1. Ensure that both Inlet and Exhaust valves are closed.
2. 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.
3. Use the handpump (if fitted) to generate pressure until the piston floats (i.e. not
touching the top or bottom travel limits.
Note
Handpump use: Slow down-strokes will only partially contribute pressure,
for higher pressurization, a faster down-stroke is required. The handpump
will generate approximately 300 psi/20 bar — above this pressure, an
external supply will be required.
Alternatively, if connected to an external supply, SLOWLY open and close
Inlet valve until piston floats. If piston is over-pressurized (piston against
top travel limit) then reduce pressure by SLOWLY opening and closing
Exhaust valve until the piston floats.
4. Gently rotate the weight stack clockwise, such that it is turning between
approximately 10 and 60 rpm. Avoid side-loads when turning the weights by placing
the palms of the hands on either side and “rolling” the stack by pulling in opposite
directions, see Figure 3-1. DO NOT rotate weights when the piston is
against the top or bottom limits of travel.
5. Allow a few moments for the system to stabilize before taking any readings,
especially after large changes in system pressure.
6. For the next, higher calibration point, repeat from step 2 above.
7. To measure reducing pressures, remove the necessary weights, and by opening and
closing the Exhaust valve, SLOWLY reduce the system pressure until the piston
floats, then rotate clockwise as above.