Examples Using Load-Sensing Hydraulic System—Power-Beyond

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Example 1 —Control valves with a load-sense provide a load-sense signal to hydraulic system and can be operated manually or by solenoids.

Example 1 is the prefered practice.

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Example 2 —Control valve directs oil into extend or retract circuits. Connect load-sense line to circuit requiring pressure. An example is a wagon lift cylinder with load supported by mechanical stops in full down position. Load-sense signals pump when increased pressure is needed. Pressure remains low when load is supported by mechanical stops.

Circuit allows cylinder "leak-down" through load-sense line (C). If leakage is not acceptable for operation, use Example 3.

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Example 3—Control valve directs oil into extend or retract circuits, either requiring high pressure. Connect load-sense line to pressure line before control valve.

System will maintain a maximum pressure of 20000 kPa (200 bar) (2900 psi) as long as power-beyond hoses are connected.

An example is a folding implement, where pressure is needed to extend or retract cylinders.

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A - Pressure Line

B - Return Line

C - Load-Sense Line

D - Control Valve

E - Cylinder

F - Pressure-Compensated Flow Valve

G - Hydraulic Motor

H - Motor Case Drain (Sump Line)

Example 4—Pressure-compensated flow control valve is used to regulate hydraulic motor speed. Connect load-sense line to pressure line after control valve.

Motor speed can fluctuate when other functions cause system pressure change. Minimize fluctuations by installing a pressure-compensated flow control valve.

For Ag high flow, it is recommended that the hydraulic motor be connected to the top SCVs (85cc high flow pump).

High flow scraper hydraulics is not recommended for motor application.

RD47322,00002D5-19-20170710