HPRV (High pressure relief valve)
LPV pumps are equipped with a combination high pressure relief and charge check valve. The high-
pressure relief function is a dissipative (with heat generation) pressure control valve for the purpose of
limiting excessive system pressures. The charge check function acts to replenish the low-pressure side of
the working loop with charge oil. Each side of the transmission loop has a dedicated HPRV valve that is
non-adjustable with a factory set pressure. When system pressure exceeds the factory setting of the
valve, oil is passed from the high pressure system loop, into the charge gallery, and into the low pressure
system loop via the charge check. The high pressure relief valve used on LPV is designed to remove
pressure spikes for short periods of time. Operating over the high pressure relief valve for extended
periods may damage the pump.
HPRV valve
P106273
Bypass function
The LPV contains a dedicated bypass valve. the bypass function is activated when the bypass valve is
mechanically backed out 3 full turns (maximum). The bypass function allows a machine or load to be
moved without rotating the pump shaft or prime mover.
Bypass valve
P106286
C
Caution
Excessive speed or extended movement will damage the pump and motor(s)
Avoid excessive speeds and extended load/vehicle movement. Do not move the load or vehicle more
than 20 % of maximum speed or for longer than 3 minutes. When the bypass function is no longer
needed, reseat the bypass valve to the normal operating position.
CPRV (Charge pressure relief valve)
An internal charge relief valve regulates charge pressure. The charge pump supplies pressure to maintain
a minimum pressure in the low side of the transmission loop.
Technical Information
LPV Axial Piston Pumps
Operation
©
Danfoss | September 2017
520L0954 | BC00000044en-US0102 | 17