SPACER 6E1444 - Caterpillar

Starting Position of the Fuel Valve
The starting position for the fuel valve is the default position when automatic control is activated. The preferred position is near the middle range of the fuel valve's travel. The default is 350 steps for the G3412 and G3516 engines. The default is 500 steps for the G3408 engine. This enables the control to maximize the amount of adjusting of the lean and rich mixtures of the air and fuel.For the reset process, the fuel valve's motor is retracted. The control retracts the motor by attempting to open the fuel valve beyond the motor's mechanical stop. In the fully retracted position, the fuel valve is fully open. The fully retracted position corresponds to zero steps. The control keeps track of the fuel valve's position.After zero steps are achieved, the control commands the motor to move the fuel valve for the number of steps that are programmed for the starting position. The default is 350 steps for the G3412 and G3516 engines. The default is 500 steps for the G3408 engine. The control keeps track of the number of steps that are moved. This enables the control to calculate the position of the fuel valve during operation. When the air/fuel mixture is richened, the control subtracts the corresponding number of steps. When the air/fuel mixture is leaned, the control adds the corresponding number of steps.Resetting the motor's position prior to engine start-up is recommended. This ensures that the starting position for automatic control is obtained and the control can determine the actual position of the fuel valve during operation.When the control is powered down, the last position of the fuel valve is recorded in non-volatile memory. Unless the fuel valve is reset to the starting position, the valve will retain the last operating position. When the motor for the fuel valve is not reset between starts of power cycles, the control may not properly display the actual position of the valve. The closed loop control system of the engine would not be affected.The reset function is prevented if the engine is operating with a load. This is done in order to avoid resetting the motor for the fuel valve when there is a risk of disturbing the operation of a loaded engine.
"F1" key
"STRT POS" key
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To reset the fuel valve to the starting position, press the "F1" key and then press the "STRT POS" key. During this process, the screen will display "MOVING STEPPER TO START POS".If an operator is not available for performing the resetting, the system is still compatible with a remote start-up. If the actual position of the fuel valve is not known, the control will work in order to maintain the desired NOX level.Entering and Exiting Setup Modes 1 and 2
Entering Setup Mode 1
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Function keysIn order to adjust parameters in setup group 1, you must enter "Setup Mode 1". To enter "Setup Mode 1", press the function keys in this sequence: "F1", "F3", "F2" and "F4".
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Entering Setup Mode