TUBE AS-TURBOCHARGER 7W7550 - Caterpillar

Table 3
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 sensor is an input 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.Switches
Pressure Switch
Illustration 5 g02332474Note: The values in Table 4 are for bench testing only. Values may not represent parameters for machine systems specifications.
Table 4
Activation Pressure 2650 200 kPa (384 29 psi)
Deactivation Pressure 2150 200 kPa (311 29 psi)
Rating + 12V ~ +32V
0.01 Amp to 1 Amp
Pressure Range 0 to 10 MPa Implement Pressure Switch
The implement pressure switch sends an input signal to the machine ECM. When the joysticks are moved from the NEUTRAL position for a boom RAISE, stick IN, stick OUT, bucket IN, or a bucket OUT operation, pilot oil is directed to the implement pressure switch. The increase of pilot pressure activates the implement pressure switch. The implement pressure switch sends an electrical signal to the machine ECM. The switch information is used to control engine speed and pump control. Also, an electrical signal from the machine ECM energizes the swing brake solenoid valve in order to release the swing parking brake.Note: The implement pressure switch does not detect a boom LOWER or a swing operation.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 6 g01158530Note: 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) Hydraulic Lock Solenoid
The hydraulic lock solenoid is an output of the Machine ECM. The hydraulic lock solenoid is energized in order to enable the primary hydraulic pressure. The hydraulic lock solenoid is de-energized in order to disable the primary hydraulic pressure.This solenoid is activated while the key switch is in the ON position and the hydraulic lock lever is in the UNLOCK position.Proportional Reducing Solenoid Valve
Illustration 7 g02703776Note: The 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) Power Shift Pressure PRV
The power shift pressure PRV is used to destroke the main pump under load to maintain engine speed. The main functions of the PRV, in conjunction with, the monitoring system,