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WIKA operating instructions model CPP1200-X
EN
14076968.02 02/2015 EN/DE
4. Design and function
Reservoir
Valve A
Hand pump
Valve B
4.4 Function
Operation of the hydraulic comparison test pump is controlled by the two valves
A
and
B
on the top of the reservoir/high pressure cylinder block. When initially priming the
system valves
A
and
B
are opened to fill the system with oil from the reservoir. Valve
B
is then closed with valve
A
left open and the spindle pump operated to provide the lower
test pressures. To provide the higher pressures valve
A
is closed to seal off the test
circuit from the low pressure part of the spindle pump and valve
B
is opened to allow the
liquid in the low pressure part of the spindle pump to return to the reservoir as the pump
is operated. This ensures that the pump can be operated without having to put large
forces on the spindle pump handwheel. To release the test pressure the spindle pump is
wound out and valve
A
is opened.