Fluke Calibration RUSKA 7615, User Manual

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Theory of Operation
The Hydraulic/Pneumatic Module
2
2-3
Table 2-1. Conversion Factors
Symbol Description Conversion Factor
inHg inches of mercury (0°C) = kPa x 0.2952998
inHg inches of mercury (60°C) = kPa x 0.296134
kPa kiloPascals = kPa x 1.0
bar bars = kPa x 0.01
psi pounds per inch2 = kPa x 0.1450377
cmH
2
O centimeters of water (4°C) = kPa x 10.19744
inH
2
O inches of water (4°C) = kPa x 4.014742
inH
2
O inches of water (20°C) = kPa x 4.021898
inH
2
O inches of water (25°C) = kPa x 4.024108
kg/cm
2
kilograms per cm
2
= kPa x 0.0101972
mmHg millimeters of mercury (0°C) = kPa x 7.500605
cmHg centimeters of mercury (0°C) = kPa x 0.7500605
knots airspeed knots per NASA TN D-822
km/hr kilometers per hour = knots x 1.852
feet feet of altitude per MIL-STD-859A
meters meters of altitude per MIL-STD-859A
user1 user defined = kPa x User defined
user2 user defined = kPa x User defined
Pa user defined (Pascals) = kPa x 1000.0
%FS user defined (percent of full scale) = kPa x 0.1450377 (for 100 psi models)
The Hydraulic/Pneumatic Module
The hydraulic/pneumatic module, shown on 2-2, houses components which generate and
accurately measures hydraulic pressure.
Pneumatic/Hydraulic Intensifier
The pneumatic/hydraulic intensifier consists of a air driven hydraulic pump which varies
the system pressure by compressing and expanding system fluid. The pump plunger is
linked to a large area piston of a pneumatic cylinder which varies its position through a
0 to 100 psi pneumatic control utilizing high speed supply and exhaust control valves.
The pump has a position sensor which tracks the position of the pump plunger. The pump
and the system is protected from the over pressure by a rupture disc. The pump pressure
is monitored by a high response pressure transducer.