COVER 2P4504 - Caterpillar

The response of the throttle actuator can be adjusted with the Caterpillar Electronic Technician (ET). The following configuration parameters are used in order to adjust the throttle response of the engine:
"Proportional Gain"
"Integral Gain"These adjustments are provided in order to obtain optimum responses to changes in the load and in the speed. The adjustments also provide stability during steady state operation.Note: Adjustment of the proportional gain directly affects the reaction speed of the throttle actuator. This problem happens when there is a difference between the actual engine speed and the desired engine speed. An excessive increase of the proportional gain may amplify instability.To adjust the proportional gain or integral gain settings for the engine, use the "Real Time Graphing" feature on the "Information" drop-down menu of Cat ET. Running a graph of the engine rpm and engine load provides the best method for observing the effects of the adjustment.After you make adjustments, always test the stability by interrupting the engine speed and/or load. The "Bump" feature on Cat ET can be used in order to provide an interruption of the engine speed. Operate the engine through the entire range of speeds and of loads in order to ensure stability.To set the proportional gain, increase the Proportional Gain until the actuator becomes unstable. Slowly reduce the Proportional Gain in order to stabilize the actuator. Use Cat ET to bump the engine speed. Observe that the engine operates properly with little overshoot or undershoot.The adjustment of Integral Gain setting dampens the actuator response to changes in load and in speed. Increasing the Integral Gain provides less damping. Decreasing the Integral Gain provides more damping. To reduce the throttle overshoot, decrease the Integral Gain. To reduce the throttle undershoot, increase the Integral Gain.Note: An increase of the Integral Gain may require a decrease of the "Proportional Gain" in order to maintain a stable operation.Repeat the adjustments of the proportional gain and of the integral gain. Continue to adjust the proportional gain and the integral gain until stability of the engine speed is achieved. Ensure that the engine responds to changes in load speed.