Case CX Series Service Training Manual page 148

TRAVEL
High Speed Travel
1) The travel-speed solenoid is energized and the swash plate angle of a travel motor is
shifted to minimum angle, high-speed travel occurs. The monitor display will indicate
high-speed (Hi).
2) The travel motors will switch to low-speed automatically at approximately 4200 psi and
switch back to high-speed when the travel pressure is reduced. The monitor display
does not change.
Note: The controller needs a RPM signal and the Travel pressure switch for High-Speed
travel.
High-speed travel occurs when the operator selects high-speed with the travel switch on the
control panel. The travel switch sends an electrical signal to the controller. The controller will
send a 24v signal to energize the travel-speed solenoid. When the valve is shifted, pilot
pressure (550/600 psi) is directed from the solenoid valve to the travel motors. The pilot
pressure shifts the 2-speed spool, which directs supply oil to shift the swash plate to
minimum angle. The travel motors will shift to low-speed when the supply pressure reaches
approximately 4200 psi. A pilot signal from the supply pressure inside the drive motors is
routed to the 2-speed spool to shift it to the low-speed position. When the supply pressure is
reduced the drive motors will shift back to high-speed. The controller will turn off the high
speed solenoid if the travel pressure drops below 580 psi to slow down travel going down a
steep grade. The travel speed solenoid valve is located in the six-solenoid valve bank. The
six-solenoid valve is located in the pump compartment.
HYDRAULICS – CX130/CX160
5 - 8
Travel Speed Solenoid
Red Wire Band
Pilot Pressure
Solenoid
CX EXCAVATORS