Location and Function
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| Illustration 1 | g00922974 |
Generator control valve (1) is located next to the exhaust duct for the ventilation system. This valve controls the amount of oil flow from the piston pump to the gear motor. This valve contains a flow control valve that will regulate the amount of oil flow that is delivered to the gear motor.
Components
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| Illustration 2 | g00922979 |
Hydraulic Schematic for the Generator Control Valve (1) Generator control valve (2) Control spool (3) on/off valve (envelope) (4) Orifice (5) Line from piston pump (system pressure) (6) Pressure tap (7) Pressure tap (8) Line to piston pump (load sensing) (9) Line to return manifold (10) Gear motor (11) Flow control (12) On/off valve (envelope) (13) Solenoid | |
The generator control valve contains the following main components:
- Control spool (2)
- Orifice (4)
- Flow control (11)
- Solenoid (13)
Operation and Oil Flow
Control Switch in the OFF Position
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| Illustration 3 | g00926069 |
Hydraulic Schematic (1) Generator control valve (2) Control spool (3) On/Off Valve (envelope) (4) Orifice (5) Line from piston pump (system pressure) (6) Pressure tap (7) Pressure tap (8) Line to piston pump (load sensing) (9) Line to return manifold (10) Gear motor (11) Flow control (13) Solenoid (AA) System pressure (AB) Sump (AC) Activated components (AD) Load sensing (AE) First pressure reduction | |
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| Illustration 4 | g00939851 |
The hydraulic circuit in Illustration 3 shows the oil flow through generator control valve (1) and to gear motor (10) when toggle switch (14) is in the OFF position.
The line to piston pump (8) goes to the load sensing valve that is in the piston pump. This load sensing valve controls the output flow of the piston pump by controlling the angle of the swashplate.
When the toggle switch is in the OFF position, On/Off valve (3) is active. When On/Off valve (3) is active, oil will bypass control spool (2). Oil will then flow through orifice (4). This orifice will only allow enough oil flow to rotate gear motor (10) at a speed of 10 to 20 rpm. This speed will help prevent corrosion from forming in the generator when the generator control valve is turned to the OFF position.
Reference: See Specifications, Systems Operation/Testing and Adjusting, "Piston Pump (Generator)" for additional information.
Control Switch in the ON Position
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| Illustration 5 | g00929341 |
Hydraulic Schematic (1) Generator control valve (2) Control spool (3) On/Off Valve (envelope) (4) Orifice (5) Line from piston pump (system pressure) (6) Pressure tap (7) Pressure tap (8) Line to piston pump (load sensing) (9) Line to return manifold (10) Gear motor (11) Flow control (12) On/Off Valve (envelope) (13) Solenoid (AA) System pressure (AB) Sump (AC) Activated components (AD) Load sensing | |
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| Illustration 6 | g00939851 |
The hydraulic circuit in Illustration 5 shows the oil flow through generator control valve (1) and to gear motor (10) when toggle switch (14) is in the ON position.
The line to piston pump (8) goes to the load sensing valve that is in the piston pump. This load sensing valve controls the output flow of the piston pump by controlling the angle of the swashplate. As a result, the piston pump will consistently produce the oil flow that is set at flow control (11) .
When the toggle switch is in the ON position, On/Off valve (12) is active. This will allow oil to flow through control spool (2) then to flow control (11). Flow control (11) should be adjusted in order to allow enough oil flow to rotate gear motor (10) at 3700 rpm. This is the speed that is necessary to generate 62 hertz.
Reference: See Specifications, Systems Operation/Testing and Adjusting, "Piston Pump (Generator)" for additional information.