How to Start, Operate and Stop Diesel Generator Set

Preparation before starting diesel generator set

① Complete inspection

a. The switch of the control panel should be turned off before inspection, and be careful not to short-circuit the battery output electrode.

b. Re-clean and inspect the machine room to ensure that there are no flammable and explosive materials around the unit, ensuring smooth and unobstructed air in and out of the machine room.

c. Thoroughly inspect and ensure that the electrical and control parts are connected correctly, in good contact, reliable, and without aging.

d. Check the reliability of the fastener and throttle adjustment system, confirm that the operating mechanisms are flexible, lightweight, and reliable, and check the pre-tightening of the water pump belt, charger belt and fan belt.

e. Clean the surface of the generating set, especially the rotating part of the unit to ensure that there are no foreign objects, check to ensure that there is no coolant, fuel, oil leakage.

② Check the oil level

Check to ensure that the oil level is between the highest and lowest marks and as close as possible to the upper limit.

③ Check fuel level

a. Note that unfiltered fuel should not be injected into the diesel engine under any circumstances.

b. Check the fuel quantity in the fuel tank and add suitable fuel if necessary.

c. When the unit starts for the first time or stops for a long time and then starts again, check to make sure there is no air in the fuel. If there is air, loosen the air bleed screw on the diesel filter and pump the fuel to the air bleed screw with the manual fuel pump, drain the air in the fuel system, and tighten the bleeder screw.

④ Cooling level

Check the coolant level to be within 5cm of the filling cover to ensure that there is no obstruction outside the radiator.

⑤ Check the air filter

a. Do not operate the diesel engine without air filter.

b. Check the air filter blockage indicator. If the indicator is red, replace the air filter.

⑥ Check battery level

Close the power switch and check the battery voltage from the control panel. If it is less than 22V and cannot meet the startup requirements, the battery needs to be charged.

⑦ Governor fuel quantity control

For the mechanical speed regulating unit, the fuel quantity control handle of the mechanical governor should be placed at the throttle position of about 800r/min; the electronic speed regulating genset does not need to be adjusted. 

Start the diesel generator set

a. Do not start the gen set with load

b. Press the start button. If the start is unsuccessful, wait for about 20 seconds before trying again. If the start is unsuccessful for 3 consecutive times, stop the start and remove the fault factors such as battery voltage or oil circuit before starting. Note that continuous start-up in a system that is not working properly will cause unburned gas to accumulate in the exhaust system, posing a potential explosion hazard.

c. For the mechanical speed regulating unit after the start of idle speed for about 1 minute, then the throttle is gradually raised to 1500r / min; electronic speed regulating unit, no need to adjust.

d. To start the diesel genset in a cold environment, preparation must be done. Use winter fuel suitable for local temperature (qualified brand). This can reduce the risk of waxy deposits in the fuel injection system. In the case of extremely low ambient temperature, it is recommended to install a preheating system (water jacket preheating, oil heating, fuel heating) and ensure that the cooling system is filled with antifreeze.

e. The battery must be in good condition. Low temperature will reduce the capacity of the battery. Depending on the actual situation, it may be necessary to increase the capacity of the battery.

f. Manual, automatic, three-remote control cabinets and ATS cabinet in non-standard units, please refer to the corresponding random data for the use of the cabinet.

Diesel generating set is in operation

a. Check the oil pressure, water temperature, voltage, frequency, etc. of the control module. If there is any abnormality, stop the machine immediately for inspection. After the fault is removed, the unit can be started again.

b. Check the oil circuit, waterway, gas circuit and smoke exhaust system of the unit for leaks. Check the connection of the unit for looseness and severe vibration. Check whether the various protection and monitoring devices of the unit are normal.

c. When the rotation speed reaches 1500r/min and the no-load operation is stable, the switch can only be closed to supply power to the load. The unit is not allowed to have continuous idle load of more than half an hour or less than 30% load operation. The gen set needs to be guarded when it is running. Overloading is strictly prohibited.

d. Do not short circuit when the unit is in operation, otherwise it will cause serious damage to the equipment. It is strictly forbidden to disassemble any parts of the generator set while it is running!

e. Do not reach under the fan shield and any other parts that have relative motion!

f. Do not try to touch the exhaust pipe, turbocharger, high temperature coolant, heater and other high temperature surfaces by hand, there is a danger of being burned!

g. Check the output voltage and frequency from the control panel. The output voltage of the unit has been adjusted at the factory, so it should be indicated within the normal range. For units with mechanical speed regulation, the frequency should be close to 52 Hz under no-load conditions; for units with electronic speed regulation or EFI speed regulation, the frequency is close to 50 Hz under no-load conditions.

h. Keep the load on the diesel generator set not exceeding the rated value. Some models can run 110% rated power continuously for 1 hour when necessary, but only after 1 hour of rated power operation.

Diesel generator set shutdown

① Genset normal shutdown

a. Stop: The unit controlled by the automatic module can stop normally by pressing the stop button by hand; the manually controlled unit can only turn the key to the “STOP” position, and can also achieve normal shutdown.

b. Before shutdown, the load must be unloaded, and it is strictly forbidden to stop with load. In general, after unloading the load, the diesel genset needs to run for 3 to 5 minutes without load before stopping.

c. When the load cable is connected or removed, the battery's negative wiring must be turned off and removed.

② Genset emergency shutdown

a. The unit must be shut down immediately if abnormal noise or odor is emitted during start-up or operation.

b. When the unit oil pressure suddenly drops to the limit or no oil pressure, the fault light is red and must stop immediately.

The machine must stop immediately:

a. When the unit water temperature suddenly rises above the specified value and the fault light is red.

b. When the unit output voltage exceeds the maximum reading on the meter.

c. When there is a fire, electric leakage or other natural disaster that may endanger the safety of the crew and operators.

At this point, press the emergency stop button or push the stop control handle of the fuel pump to the stop position rapidly , the unit will quickly cut off the load, and immediately turn off the throttle, while the red "emergency stop" indicator light is on. The button needs to be re-screwed to release the emergency stop signal. When the power generating set is in normal operation or is supplying power to the equipment, if there is no special emergency, it is recommended that the user do not perform emergency shutdown operation at will.

After shutdown

a. Check for leaks in the engine and machine room.

b. Close the fuel valve

c. If the unit is to stop for a period of time, turn off the main switch.

d. Long-term shutdown should drain fuel and cooling water, and periodically charge the battery according to maintenance specifications.

e. When the ambient temperature is lower than 5°C, the unit after shutdown must do antifreeze measures to avoid freezing cracking of the body and water tank.