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Optional Orifices: T4, T5, T6, U6, U7
T4
T6
T5
U7
U6
P106 415E
Brake Pressure Defeat (BPD) Option
The PCOR function can be equipped with an optional brake pressure defeat (BPD) option that defeats the
PCOR operation during dynamic braking. A shuttle spool ahead of the PCOR valve directs only
acceleration system pressure to the PCOR. During deceleration the dynamic braking pressure is blocked
from the PCOR limiting rapid deceleration, uncontrolled pressures or engine over-speeding while the
vehicle/machine is slowing down. An external hydraulic signal pressure fed to ports XA or XB are required
to operate the BPD spool. PCOR operation on one system pressure side is also an option.
BPD Option
Shuttle valve
Brake defeat spool
PCOR spool
P106 431E
PCOR adjuster
Service Manual
Series 51 Hydraulic Proportional Controls Service Manual
Introduction
11009446 • Rev BA • July 2014
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