HOUSING AS 2801576 - Caterpillar

Solenoid (Auxiliary #2 Valve Port A and B Solenoids)
The implement ECM will use the auxiliary hydraulics 2 port a and b solenoids to set the line relief pressure for the auxiliary valve. The ECM will set the line relief pressure 35 5 bar (507.5 72.5 psi) above the configured maximum load sensing pressure for the port. The relief pressure function protects the tool from externally generated high pressures.Solenoid (Auxiliary Valve Port A and B Flow Solenoids)
The auxiliary valve port "A" and port "B" flow solenoids are used to control the hydraulic flow from port "A" and port "B" on the MCV valve.The machine ECM will use the PWM input signal from the right joystick thumbwheel or from the left attachment foot pedal position sensor in order to control the output for the flow solenoids.The maximum flow setting can be configured in the monitor "Tool Program" menu or by using Cat ET. The maximum flow value range that can be configured is 0 l/min (0 us gpm) to 270 l/min (71.3 us gpm).Solenoid (Auxiliary Valve Load Sensing)
The load sensing solenoid is used by the ECM to set the maximum pressure of the auxiliary hydraulic system.The maximum load sensing pressure setting for port "A" and port "B" can be configured in the monitor "tool program" menu or by using Cat et. The configurable range of load sensing pressure that can be configured is from 0 kpa (0.0 psi) to 35000 kpa (5076 psi).The ECM will adjust the electrical current of the pwm output for the load sensing solenoid in order to maintain the configured maximum system pressure for a specific tool.On/Off Solenoids
For control of on/off type solenoids and relays, the ECM will either turn ON or turn OFF the output for a component. The output command is based on the signals from the input devices that are involved in the system. The ECM will not vary the amplitude of the output, the circuit is either energized (on) or the circuit is de-energized (off). When the on/off output circuit is energized, most often system power will be used to energize the circuit and the output component.
Illustration 7 g01158530Note: The values in Table 3 are for bench testing only. Values may not represent parameters for machine systems specifications.
Table 3
Rated Voltage 24 VDC
Coil Resistance 32.0 3.2Ω (T=20° C) The work tool system contains the auxiliary valve directional valve and quick coupler solenoids.Solenoid (Auxiliary Valve Directional)
The directional solenoid is controlled as an on/off solenoid.When a tool is configured in the tool program, the tool must be noted as either a uni-directional tool (one-way flow) or a bi-directional tool (two-way flow). The ECM will use the directional solenoid to set the valve for either the one way or the two-way flow.When a uni-directional tool is selected, the ECM will energize the directional solenoid in order to open a return