Understanding Hydraulic Depth Control System-Series-Parallel

NOTE: Series-parallel hydraulic system applies to wide FLEX-FOLD machines ONLY.

1. Center frame (control) cylinders (A) and wing (slave) cylinders (B and C) are in series with each other.

2. As hydraulic oil is pumped into base ends of master cylinders, oil is forced out of rod ends and into base ends of slave cylinders.

3. As oil enters base ends of slave cylinders, displaced oil from rod ends returns to tractor.

4. To compensate for smaller volume of oil in rod ends of cylinder, slave cylinders are 6.4 mm (1/4 in.) smaller in diameter than master cylinders.

5. As machine is raised and cylinders are completely extended, slave cylinders will become synchronized with master cylinders. This maintains uniform height across machine.

N37225


A-Master Depth Control Cylinders
B-Right-Hand Wing Depth Control Cylinder (Slave)
C-Left-Hand Wing Depth Control Cylinder (Slave)

AG,OUO1011,2683 -19-29MAR00-1/2

6. Synchronization is accomplished by a small orifice at rod end of each cylinder. When piston seal passes by orifice (cylinder fully extended), pressure oil (A) can then be bypassed from BASE ends of master cylinders to base ends of slave cylinders. When slave cylinder rods are fully extended, return oil (B) passes from BASE ends of slave cylinders back to tractor.

7. For synchronization to be accomplished, depth control must be held for a few seconds with cylinders fully extended to allow passage of oil through system.

8. After oil has "rephased" the system, leave depth control lever (or switch) in neutral position for at least three seconds to allow all cylinders to retract far enough to close rephase passages and completely synchronize system.

N58906


A-Pressure Oil
B-Return Oil

AG,OUO1011,2683 -19-29MAR00-2/2