INSULATION 5271807 - Caterpillar

During normal turning operation, the traction control valves are not activated. The speed sensors in each motor send a signal to the ECM so that the ECM can monitor the individual speed of each drum half. The ECM allows a predetermined amount of speed differential between the drum halves of each drum in order to allow the two drum halves to turn at independent rates. This will help prevent marking of the mat. The ECM does not send a signal to the solenoids in order to activate flow to the motors during this time. Also, the ECM does not send a signal to the solenoids in order to regulate flow to the motors during this time. If the speed differential between the two halves of the drum exceeds the set parameter in the software program due to a loss of traction, the ECM will activate the correct solenoid in order to restrict flow to the drum half with the higher speed. Activation of the foot switch causes the program to use a new set of programmed parameters. This allows less speed differential between the drum halves. The ECM will then activate the solenoids for the control valves. Therefore, the traction control switch should not be activated when the machine is turning corners. The traction control switch should only be used in the following situations:
propelling in a straight direction
difficult to get traction
no allowable slippage of the drumOffset System
Illustration 5 g00937856
(A) OffsetThe offset system is an optional system that allows the front drum to be offset from the rear drum. Refer to Illustration 5. This option increases the mobility of the machine when you are maneuvering.Hydraulic oil enters the offset system from the steering pump. A priority valve directs flow to the drum offset valve as oil is required. Excess oil is sent to the fan motor. The drum offset valve controls the flow of oil to the offset cylinder. The return oil from the offset cylinder passes back through the drum offset valve to the hydraulic oil tank.HOLD
Illustration 6 g00937399
Hydraulic Schematic of the Offset System (1) Pilot opened check valves (2) Priority valve (3) Offset cylinder (4) Relief valve (5) Drum offset valve (AA) System pressure