TM2361 (24JUN08) 9010-05-20 450DLC Excavator Operation and Tests 062608 PN=268 Theory of Operation The engine speed is controlled by the following items: • Engine Speed Dial (R15) • HP (high power) Mode (S12) • P (standard) Mode (S12) • E (economy) Mode (S12) • Travel HP Mode Control • Auto-Idle Control (S8) Engine Speed Dial The purpose of the engine speed dial is to control the engine rpm via operator input. The main controller uses these input signals to determine appropriate engine speed:
9010 05 20 • Engine Speed Dial (R15) • Auto/Idle Switch (S8) • Boom Up Pressure Sensor (B52) • Boom Down Pressure Sensor (B53) –UN–16DEC05 • Arm Out Pressure Sensor (B50) • Arm In Pressure Sensor (B51) • Bucket Dump Pressure Sensor (B55) • Bucket Curl Pressure Sensor (B54) TX1000033 • Swing Pressure Sensor (B33) • Travel Right Pressure Sensor (B56) • Travel Left Pressure Sensor (B57) Switch Panel • Attachment Pressure Sensor (B45) • Counterweight Removal Pressure Sensor (B46) R15—Engine Speed Dial S8—Auto Idle Switch S9—Windshield Wiper and Washer Switch The main controller then sends a signal via controller area S10—Work Light Switch network (CAN) to the engine control module (ECM), and S11—Travel Speed Switch the ECM then sets engine rpm.
S12—Power Mode Switch HP (high power) Mode The purpose of the HP mode is to increase engine speed while performing certain dig functions. The Main Controller (MC) sends a signal to the ECM via CAN communication to raise engine rpm when the following conditions are met: • Power mode switch is turned to the HP mode position. • Engine speed is 1020 rpm or higher. • Arm in, boom up, or a combination of both functions actuated. • Pump delivery pressure high. Continued on next page JC89288,0000192 –19–27JAN06–2/4