A hydraulic system with a pressure reducing valve, said pressure reducing valve comprising: an inlet side tank connection and a first inlet side system pressure connection,Check Valves and an outlet side working pressure connection that is selectively connected to the first inlet side system pressure connection or to the tank connection through the pressure reducing valve, wherein the valve includes a second inlet side system pressure connection that is pressurized at a different pressure level than that of the first system pressure connection and that is selectively connected to the working pressure connection through the pressure reducing valve.Reducing Valves Briefly stated, in accordance with one aspect of the present invention, a hydraulic system with a pressure reducing valve having a tank connection, a system pressure connection, and a working pressure connection,MULTI-FUNCTIONAL WATER PUMP CONTROL VALVE is connected to the system pressure connection or to the tank connection through the pressure reducing valve. The pressure reducing valve has a second system pressure connection that is at a significantly higher pressure than the first system pressure connection and is connected to the working pressure connection through the pressure reducing valve. The tank connection is connected to a tank that contains a working medium, such as hydraulic oil, which is at a tank pressure, preferably ambient pressure. In accordance with an essential aspect of the present invention the two system pressure connections are at different system pressures, both of which are greater than the tank pressure or the ambient pressure. At least one hydraulic system component is connected to the working pressure connection. The hydraulic system component is preferably a clutch that is initially charged at a relatively low system pressure and can be actuated with the relatively high second system pressure as needed. A preferred exemplary embodiment of the hydraulic system is characterized in that the first system pressure connection is under low pressure and the second system pressure connection is under high pressure. The low pressure is, for example 5 to 10 bar, and can be produced with a low- pressure pump. The high pressure is preferably more than 30 bar, for example 45 bar, and can be produced with a high- pressure pump. Another preferred exemplary embodiment of the hydraulic system is characterized in that the pressure- reducing valve is a 4/3 directional valve. The 4/3 directional valve has four connections: the working pressure connection, the tank connection, and the two system pressure connections. The working pressure connection can be connected to the tank connection, the first system pressure connection, or the second system pressure connection, in three different selector positions of the pressure reducing valve.

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