ALTERNATOR GP-CHARGING 1264298 - Caterpillar

Modulating Valve (Auxiliary Hydraulics)
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Modulating valve (auxiliary hydraulics)
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Location of the modulating valves for the auxiliary hydraulics The modulating valves are located behind the work tool control. The auxiliary hydraulic ECM activates the auxiliary hydraulic solenoids. There are two auxiliary hydraulic solenoids. The solenoids are referred to as A1 and A2. The solenoids control the pilot pressure for the auxiliary hydraulics. The solenoids are proportional. These solenoids receive a proportional current from the ECM that is from 0 Amperes to 1.8 Amperes on the standard machine and 0 Amperes to 2.0 Amperes on the XPS high flow machines.Solenoid Valve (Two Speed)
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Solenoid valve (two speed)
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Location of the solenoid valve (two speed)The solenoid valve for the two speed is located beneath the cab next to the parking brake solenoid.The auxiliary hydraulic ECM will activate the solenoid valve for the two speed. The valve will block the flow of hydraulic oil to half of the pistons in the hydraulic motors. High Flow Valve
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High Flow Valve (1) C+/C- Solenoids (2) Control flow solenoid (3) High flow solenoid
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Location of the high flow valveThe high flow valve is located under the floor plate at the front of the machine. The high flow valve contains the circuits for the high flow and worktool control circuits.Solenoid Valve (High Flow)
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The ECM controls the high flow solenoid in order to provide a higher amount of hydraulic flow. When the high flow solenoid is energized, flow from the high flow gear pump is blocked to the tank, causing pressure to build.Modulating Valve (Control Flow) for High Flow Machines
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The control flow solenoid directs the pump supply oil to either the worktool control or the high flow system. When the control flow solenoid is energized, some of the flow from the high flow pump is directed to open the check valve in the circuit to the auxiliary worktool.Modulating Valve (Control Flow) for (XPS) High Flow Machines
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The solenoid valve for the control flow is located beneath the cab. If a high flow worktool is detected and the C+/C- functions or the worktool pressure switch are not activated, the auxiliary hydraulic ECM will activate the control flow solenoid.