I. SPEED, GAIN and STABILITY Adjustment Methods
The rated SPEED set by the GAC speed control board at the factory is generally around the idle speed range. After starting the unit, adjust the speed potentiometer. Turning clockwise accelerates and turning counterclockwise decelerates. Adjust it to the required rated speed.
If the unit has a runaway situation during acceleration, first adjust the GAIN and STABILITY counterclockwise until the unit is temporarily stable, and then adjust the SPEED potentiometer to the required rated speed.
After the unit reaches the rated speed, first adjust the GAIN potentiometer. Rotate it clockwise until the unit starts running, then counterclockwise until the unit just stabilizes. After it stabilizes, make a slight counterclockwise adjustment. The adjustment method for the STABILITY potentiometer is the same.
After adjustment, push the actuator's push rod. If there is a runaway situation, fine-tuning the GAIN and STABILITY potentiometers counterclockwise until the unit is stable. Push the actuator push rod again. If there is a slow recovery, it is because the GAIN potentiometer is set too low. You can slightly adjust the GAIN potentiometer clockwise. If the unit recovers quickly and there is no runaway, then the SPEED (speed), GAIN (gain), and STABILITY (stability) adjustments have been completed.
II. IDLE Adjustment Method
When adjusting the idle speed, the connection points of different speed control boards are also different. Please carefully check the circuit diagram and manual of the speed control board before adjusting the idle speed. Take ESD5500 as an example.
After the unit starts, short-circuit the M terminal and G terminal on the speed control board. The unit speed will drop to the IDLE speed set by the GAC factory. Then adjust the IDLE potentiometer. Clockwise rotation accelerates and counterclockwise rotation decelerates. Adjust it to the idle speed you need.
After the short-circuit connection between terminal M and terminal G is disconnected, the unit returns to its rated speed.
III. Adjustment Method of OVER SPEED Protection
Take ESD5221 as an example. The speed control board with overspeed protection function will have two relay alarm outputs, one normally open point and one normally closed point. (You can first connect these two points to the throttle solenoid valve of the unit or the relay that controls the solenoid valve.
The factory setting value of the overspeed protection is 10% (that is, exceeding the rated speed by 10%, for example, if the rated speed is 1500RPM, the protection value is 1650RPM). The adjustment method to enable this overspeed protection value is: First, adjust the SPEED, GAIN and STABILITY to the best operating state of the unit. Hold down the TEST button and adjust the OVER SPEED potentiometer. Rotate counterclockwise until the overspeed protection indicator red light on the speed control board lights up, the normally open point of the alarm output closes and the normally closed point opens. (If the alarm point reports to the throttle, the unit should stop and alarm.) Then press the RESET button to reset the fault and start the unit again. The 10% overspeed protection value will be activated.
If the overspeed protection value is 15% or any other value, the setting method is: (Take 15% as an example) First, turn the OVER SPEED potentiometer clockwise a little higher or to the middle position. Then, rotate the SPEED potentiometer to adjust the rotational SPEED to 1725RPM. After that, turn the OVER SPEED potentiometer counterclockwise until the overspeed protection indicator red light on the speed control board lights up. The normally open point of the alarm output closes and the normally closed point opens (if the alarm point reports to the throttle, the unit should shut down and alarm). Then press the RESET button to reset the fault and start the unit again. The 15% overspeed protection value is set.
IV. Adjustment Methods for STARTING FUEL and SPEED RAMPING
The smokeless start-up of the ESD5500 and ESD5300 series in the GAC speed control board all uses this adjustment method. Take the ESD5500E as an example. When adjusting, first turn the STARTING FUEL clockwise to the maximum and the SPEED RAMPING counterclockwise to the minimum. Then start the unit normally (start at the rated speed), short-circuit the M terminal and G terminal to reduce the unit speed to idle speed, and adjust the idle speed. If the idle speed operation is abnormal, adjust the GAIN and STABILITY potentiometers (the prerequisite for adjusting the GAIN and STABILITY of the idle speed is that the unit operates normally at the rated speed). After adjustment, rotate the STARTING FUEL potentiometer counterclockwise until the unit has a significant and sudden drop in speed. At this point, turn clockwise to the idle speed you just ran, and then make a slight clockwise adjustment. The STARTING FUEL potentiometer will be adjusted. The SPEED RAMPING potentiometer adjusts the time it takes for the idle speed to rise to the rated speed. Rotating counterclockwise to the bottom takes the shortest rising time, and vice versa takes the longest rising time. The rising time varies depending on the engine. The maximum rising time is more than 20 seconds. The longer the time, the smaller the smoke volume; vice versa, the smoke volume is larger. Disconnect the short-circuit wire between the M terminal and the G terminal to observe whether the smoke exhaust volume is normal at this time. If the smoke exhaust volume is abnormal, fine-adjust the SPEED RAMPING potentiometer clockwise or counterclockwise to control the speed-up time and adjust it to the smoke exhaust volume satisfactory to the user.
V. DROOP Method
Take GAC ESD5500E as an example. Before adjustment, a load sufficient to meet the full-load requirements of the unit should be prepared. If the accuracy requirement for the percentage of the adjustment rate is not high, simply short-circuit the K terminal and the L terminal, and then adjust the DROOP potentiometer counterclockwise by one eighth of a turn. The speed control board will then have an adjustment rate.
If the precision of the rate adjustment is required to be high, for instance, a 3% rate adjustment is needed, first short-circuit the K terminal and L terminal, approximately rotate the DROOP potentiometer to the middle position, and then adjust the unit speed to 1545RPM under no-load conditions. After that, fully load it. If the DROOP is adjusted just right, the unit speed at full load should be 1500RPM. If not, For instance, if the speed is only 1355RPM, slightly adjust the DROOP potentiometer counterclockwise, then unload the load to zero. If the DROOP is adjusted just right, the no-load speed should be 1545RPM. If not, for example, only 1534RPM, then precisely adjust the speed to 1545RPM and then increase it to full load. The speed should be 1500RPM. If not, for example, 1532RPM, then the DROOP potentiometer was adjusted counterclockwise a little too much just now. Now, fine-adjust the DROOP potential clockwise a little bit, and then unload the load to zero. The speed should be 1545RPM. If not, precisely adjust the speed to 1545RPM again, and then fully load it. The speed should be 1500RPM. If the speed is exactly 1500RPM, that's normal. Then, when the load is unloaded to zero, the speed should be 1545RPM. If so, the 3% speed adjustment is completed.
For a unit rated at 1500RPM, to adjust the SPEED to 3%, short-circuit the K terminal and L terminal. When the unit is no-load, adjust the speed potentiometer to the speed at which the speed is increased. The speed for 3% speed adjustment: 1500+1500×0.03=1545RPM. When fully loaded, the rotational speed should be 1500RPM. If it is lower than 1500RPM, finely adjust the DROOP potentiometer counterclockwise (the adjustment amount depends on experience). If it is higher than 1500RPM, finely adjust the DROOP potentiometer clockwise (the adjustment amount depends on experience). Unload The no-load SPEED should be 1545RPM. If the speed is not adjusted to 1545RPM using the speed potentiometer; Repeat this several times until the no-load speed reaches 1545RPM and the full-load speed reaches 1500RPM. This indicates that the speed adjustment rate is 3%.
Note: This is a rather complex adjustment method, but it is also the only way to achieve a highly accurate rate adjustment. When setting the rate adjustment, the operation of the unit must be normal!
Six: What should be done when the crew is traveling
When a slow-moving trolley appears in the unit with an amplitude of more than 3 Hertz, first check the mechanical parts of the unit, such as whether there is friction between the oil pump, the actuator and the connecting rod of the oil pump, and other places. After checking all these parts, adjust the GAIN and STABILITY potentiometers. If the adjustment is ineffective, check if there is a SOFT connection between the units. For example, if the generator has double bearings, there will be a soft joint between the generator and the engine. Then turn on the SOFT COUPLING C2 switch and observe whether the units are stable. The LEAD CIRCUIT C1 switch is set to the critical position when the GAIN potentiometer is adjusted to the minimum and the unit still cannot stabilize. After the two switches are set, the unit improves a little but still runs. Then readjust the GAING and STABILITY potentiometers again. After readjust, the unit is still unstable. Then perform the second-level differential control.
The second-level differential control: After the C1 switch is turned off, the unit runs as usual. First, check if the mechanical parts are normal. After all mechanical parts are checked and found to be normal, cut the connection wire between E1 and E2 on the DROOP potentiometer. The situation of the unit running should be significantly reduced. Then, readjust the GAIN and STABILITY potentiometers. If the unit still runs, Please contact the manufacturer.