AS4251C Asphalt Paver Operator Controls - Main Control Panel Caterpillar

Illustration 1	g01394731
(1) Power crown control (2) Tamper bar's speed (3) Tamper bar's ramp time (4) Counterbalance system's pressure gauge (5) Counterbalance system's pressure adjustment in standby mode (6) Counterbalance system's pressure adjustment in paving mode (7) Auger raise/lower control (8) Vibration frequency (9) Spray down

Power Crown Control (1)

Power crown control - Press and hold switch (1) upward in order to increase the screed's crown. Press and hold switch (1) downward in order to decrease the screed's crown.

Note: When you release switch (1) the switch will return to the center position. The screed's crown will remain in the last selected position.

Tamper Bar's Speed (2)

Tamper bar's speed - Knob (2) controls the speed of the tamper bar while the machine is working in AUTOMATIC mode or MANUAL mode. Turn knob (2) counterclockwise in order to decrease the speed of the tamper bar. Turn knob (2) clockwise in order to increase the speed of the tamper bar.

Tamper Bar's Ramp Time (3)

Tamper bar's ramp time - Use knob (3) to control the ramp time for the tamper bar. The tamper bar's ramp time is used in order to prevent the screed from leaving a mark on the mat when you increase the machine's speed. When the knob is turned counterclockwise, the tamper bar's ramp time is set to zero. If the tamper bar's ramp time is set at zero, the tamper bar will start at the speed that is set by knob (2). When you turn the knob (3) clockwise, the ramp function is enabled. Turn knob (3) clockwise in order to increase the amount of time for the tamper bar to ramp up to the set speed.

Counterbalance System's Pressure Gauge (4)

The pressure gauge (4) displays the hydraulic pressure for the screed's counterbalance system.

Counterbalance System's Pressure Adjustment (5) (6)

The screed counterbalance system applies an upward force on the screed in order to reduce the effective weight of the screed. There are two different controls for the counterbalance system. Use the appropriate control when you adjust the operating pressure.

Standby Mode - Use knob (5) when the machine is in the STANDBY operating mode. Turn knob (5) clockwise in order to increase the pressure for the screed's counterbalance system. When you increase the pressure you reduce the effective weight of the screed. Turn knob (5) counterclockwise in order to decrease the pressure. The optimum setting for the screed's counterbalance system will depend on the asphalt and the operating conditions at each job site.

Paving Mode - Use knob (6) when the machine is in the PAVING operating mode. Turn knob (5) clockwise in order to increase the pressure for the screed's counterbalance system. When you increase the pressure you reduce the effective weight of the screed. Turn knob (5) counterclockwise in order to decrease the pressure. The optimum setting for the screed's counterbalance system will depend on the asphalt and the operating conditions at each job site.

Auger Raise/Lower Control 7

Auger raise/lower control - Press and hold switch (7) upward in order to raise the machine's augers. Press and hold the switch (7) downward in order to lower the machine's augers. When you release switch (7), the machine's augers will remain in the last selected position.

Vibration Frequency 8

Vibration Frequency - Turn knob (8) clockwise in order to increase the frequency for the screed's vibratory system. Turn knob (8) counterclockwise in order to decrease the frequency of the screed's vibratory system.

Spray Down 9

Spray Down - Move switch (9) upward in order to activate the spray down for the machine. Move the switch (9) downward in order to deactivate the spray down for the machine.