OM3023 10/00 Operation - Section 3 Operating Instructions Page 3-27 The tap up and tap down operations are used for making fine adjustment of the set travel speed. To Cancel Set Travel If the cancel switch is operated for more that 1 second, the control is stopped. When this happens, the travel speed display shows 0. It is possible to adjust the set travel speed 5 km/h (3.1 MPH) when traveling in ARSC (when the accel- erator pedal is released). When the accelerator pedal is being depressed, the ARSC is canceled, so it is possible to operate freely in a range from 10 to 55 km/h (from 6.2 to 34.2 MPH). OR If the system switch is turned OFF, the control is canceled.
When this happens, the travel speed display goes out. To Increase Set Speed NOTE: The switch must be operated for at least 1 second (different from other switches) to cancel the control. This is to prevent any problem of the control being canceled if the switch is touched by mistake. If it is desired to increase the set speed, depress the accelerator pedal to increase speed, and when the desired set travel speed is reached, press the set switch on the ARSC set lever. The set travel speed will be changed to the new speed.
Relationship With Exhaust Brake To Decrease Set Speed If the exhaust brake switch is at the ON position, the exhaust brake is actuated in the normal way when the accelerator pedal is released if the torque con- verter lock-up is ON. If the machine attempts to travel at a speed greater that the set speed, the ARSC is actuated. If it is desired to decrease the set speed, operate the retarder control lever to reduce speed, and when the desired set travel speed is reached, press the set switch on the ARSC set lever. The set travel speed will be changed to the new speed. If the exhaust brake switch is at the OFF position, the exhaust brake is not actuated when the ARSC is being operated.
If the foot brake or retarder control lever are operated, the exhaust brake is actuated in the same way as normal. NOTE: After using the retarder control lever to reduce the speed, return it to its original position. Traveling Again At Set Speed If the downhill slope is not steep and the engine brake and exhaust brake have ample effect, the machine will not accelerate to the set travel speed, so the ARSC may not be actuated. If the machine repeatedly travels on the same slope, once the travel speed has been set, it is possible to operate the ARSC without carrying out the setting operation each time.
Before entering a downhill slope, if the travel speed has been adjusted to a speed lower that the set speed displayed on the travel speed display, the READY lamp (green) lights and the ARSC is actu- ated when the accelerator pedal is released. Recommended Set Speed Set the travel speed so that the engine speed is at least 1800 rpm, and travel so that the retarder oil temperature gauge is in the green range. If there is danger that the retarder oil may overheat, the ARSC caution lamp will illuminate and the set travel speed is automatically reduced. NOTE:
When traveling at a speed greater than the set speed displayed on the travel speed display, the ARSC is not actuated even when the accelerator pedal is released. When this happens, the READY lamp (green) also does not light up. Always adjust the travel speed to a speed lower that the set speed displayed on the travel speed display, and check that the READY lamp lights up.