HOUSING-FLYWHEEL 1006549 - Caterpillar

The values in Table 4 are for bench testing only. Values may not represent parameters for machine systems specifications.
Table 4
Operating Pressure     50 MPa    
Supply Voltage     +7V ~ +14V    
Output Signal     500 100 Hz (PWM)    
Output Range     5% ~ 95%    Drive Pump Pressure Sensor and Idler Pump Pressure Sensor
The drive pump pressure sensor and idler pump pressure sensors are inputs to the machine ECM. The drive pump and idler pump pressure sensors are located on the main control valve. The drive pump pressure sensor monitors the pressure of the drive pump oil in the front half of the main control valve high-pressure passages. The idler pump pressure sensor monitors the idler pump oil pressure in the rear half of the main control valve high-pressure passages. The pressure sensors send a pulse width modulated (PWM) input to the machine ECM. This pressure information is used for pump control and travel speed.Outputs
The ECM responds to decisions by sending electrical signals to the outputs. The outputs can create an action or the outputs can provide information to the operator or the service technician.Solenoids
On/Off Solenoids
Illustration 5 g01158530
The values in Table 5 are for bench testing only. Values may not represent parameters for machine systems specifications.
Table 5
Rated Voltage     24 VDC    
Coil Resistance     32.0 3.2Ω (T=20° C)    Straight Travel Solenoid
The straight travel solenoid is energized to maintain straight travel even though a swing operation or implement operation is performed during travel.The straight travel solenoid ensures straight travel of the machine when other circuits are operated during travel. The machine ECM recognizes the input status of the right travel pressure switch, left travel pressure switch, and the implement pressure switch. When all three pressure switches are activated to the ON position, the machine ECM activates the straight travel solenoid. Straight travel is now maintained.For more information on the straight travel solenoid, refer to Systems Operation, "Control Valve (Straight Travel)".Swing Priority Solenoid
When swing priority is activated, the output flow from the idler pump supplies hydraulic oil to the swing hydraulic circuit. Since swing priority increases the swing acceleration, swing priority is useful for loading operations. Swing priority is also useful for leveling operations and trenching operations when higher swing force is required.The machine ECM uses the swing control pressure sensor to control the swing priority solenoid. Whenever the pilot pressure exceeds 2750 kPa (400 psi) the machine ECM de-activates swing priority solenoid in order to enable swing priority.For more information on the swing priority solenoid, refer to Systems Operation, "Swing System".Reverse Proportional Reducing Solenoid Valve
Illustration 6 g02304374
Valve cutaway, hydraulic schematic symbol, and electrical connector designationThe values in Table 6 are for bench testing only. Values may not represent parameters for machine systems specifications.
Table 6
Current Range     0 mA ~ 700 mA    
Coil Resistance     11.5 0.5Ω (T=20° C)    
Illustration 7 g02304414
Reverse PRV's have the P-port open to the A-port with no current applied. Therefore, the machine ECM applies current to the PRV in