Sweep System, Side Broom 191Service Manual – SW8000Electrical CircuitMost electrical control circuits are fairly straight forward with the controller completing the electricalcircuits to ground. The controller will not activate the side brooms unless the main broom is active (and allother prerequisites to that function are also true).Hydraulic Circuit, Brooms OffWhen the side brooms are not active, the lift cylinders are held in the lifted state and no fluid flows tothe motors. The hydraulically controlled valve V1 is in the inactive state because S3 is also inactive, andno hydraulic pressure is present on the control circuit. This also sets the pilot controlled check valve C2inactive, so it functions as a normal check valve. This check valve keeps the brooms in the lifted state even ifthe hydraulic system is shut down.Piloted check valve C1 is active, and this allows fluid to pass backward through the check valve to drainexcess fluid from the second (optional) lift cylinder. Excess fluid from the first lift cylinder flows through theinactive S3 valve to return to the sump.In the event that the main broom is running without the side brooms, the S3 valve also contains a sidebroom bypass circuit to permit excess fluid not needed by the main broom to return to the low pressurereturn line.EXCFINFilter CoolerPressureReliefSlave to S3 Side BroomBypassDual BroomOptionHopper Up /Sweep BypassMain BroomFlow SpliterEngineSumpFlow SpliterMainBroomSide Broom LiftSide Broom LiftSide BroomSide BroomTo SteeringSide BroomBypassSpeedControlV1C2C1Side Brooms Raised,Motors InactiveReverseFloww/ Pressurew/o PressurePilot ControlledCheck ValveLow PressureSump ReturnFlow DirectionPilot / ControlHigh Pressure
