Basic knowledge of diesel generator set

Basic knowledge of diesel generator set

We are a manufacturer in China – PowerSUM

Let’s popularize the knowledge of diesel generator set.

  1. Which six systems are included in the basic equipment of diesel generator set?

(1) Oil lubrication system;

(2) Fuel system;

(3) Control and protection system;

(4) Cooling and heat dissipation system;

(5) Exhaust system;

(6) Start the system.

  1. Why does the engine oil and oil filter need to be replaced after a period of use?

During the running in period of a new engine, impurities inevitably enter the oil pan, causing physical or chemical changes in the oil and oil filter. In the process of after-sales customer service for the units sold by Everbright Smart Energy, we will assign professionals to carry out relevant maintenance for you.

  1. Why do we ask customers to tilt down the smoke exhaust pipe 5-10 degrees when installing the unit?

It is mainly to prevent rainwater from entering the smoke exhaust pipe, leading to major accidents.

  1. Generally, diesel engines are equipped with manual oil pumps and exhaust bolts. What are their functions?

It is used to exhaust the air in the fuel pipe before the engine.

  1. What is the automation level of diesel generator set?

Manual, self starting, self starting plus automatic mains power conversion cabinet, remote three remote (remote control, telemetering, remote monitoring)

  1. Why is the outgoing line voltage standard of the generator 400V instead of 380V?

Because the outgoing line has voltage drop loss.

  1. What is the requirement that the use site of diesel generator set must have smooth air?

The output of diesel engine is directly affected by the quantity and quality of air inhaled, and the generator must have sufficient air for cooling. Therefore, the site must have smooth air.

  1. Why should we not use tools to screw the above three devices too tightly when installing oil filter, diesel filter and oil-water separator, but only use hand to screw them until no oil leakage occurs?

Because if the seal ring is screwed too tight, it will expand and generate great stress under the action of oil bubble and body temperature rise. Damage to the filter housing or separator housing itself. What is more serious is that it causes the damage of the body nut which cannot be repaired.

  1. After purchasing a diesel generator set, which three points should be verified first?

1) Verify the true useful power of the unit. Then determine economic power and standby power. The method for verifying the true useful power of the unit is: multiply the 12 hour rated power of the diesel engine by 0.9 to get a data (kw). If the rated power of the generator is less than or equal to this data, then the rated power of the generator is determined as the true useful power of the unit. If the rated power of the generator is greater than this data, then this data must be used as the true useful power of the unit.

2) Verify which self-protection functions the unit has.

3) Verify whether the power wiring of the unit is qualified, whether the protective grounding is reliable, and whether the three-phase load is basically balanced.

  1. There is an elevator starting motor of 22KW. How large a generator set should be equipped?

22 * 7=154KW (the elevator is a direct loaded starting model, and the instantaneous starting current is generally 7 times of the rated current to ensure the elevator to move at a constant speed). (i.e. at least 154KW generator set shall be equipped)

  1. How to calculate the optimal use power (economic power) of the generator set?

P optimal=3/4 * P rated (i.e. 0.75 times rated power).

  1. How much higher is the engine power of the general generator set than the generator power according to the national regulations?

According to national regulations, the engine power of general generator set shall be 10% higher than the generator power.

  1. The engine power of some generator sets is expressed in horsepower. How to convert horsepower to international unit kilowatt?

1 HP=0.735 kW, 1 kW=1.36 HP.

  1. What is the relationship between apparent power, active power, rated power, maximum power and economic power?

1) The unit of apparent power is KVA, which is used to express the capacity of transformer and UPS in China.

2) The active power is 0.8 times of the apparent power, and the unit is KW. It is used for power generation equipment and electrical equipment in China.

3) The rated power of diesel generator set refers to the power that can operate continuously for 12 hours.

4) The maximum power is 1.1 times of the rated power, but only 1 hour is allowed within 12 hours.

5) Economic power is 0.75 times of rated power, which is the output power of diesel generator set that can operate for a long time without time limit. When operating at this power, the fuel consumption is the lowest and the failure rate is the lowest.

  1. Why not allow the diesel generator set to operate for a long time when the power is lower than 50% of the rated power.

The engine oil consumption increases, the diesel engine is easy to deposit carbon, the failure rate increases, and the overhaul cycle is shortened.

  1. Is the actual output power of the generator in operation based on the power meter or the ammeter?

The ammeter shall prevail, and the power meter is only for reference.

  1. How to deal with the loss of excitation of the generator?

The generator is not used for a long time, resulting in the loss of residual magnetism contained in the iron core before leaving the factory, and the excitation coil cannot establish the due magnetic field. At this time, the engine operates normally but cannot generate power.

Handling method:

1) If there is an excitation button, press the excitation button once;

2) If there is no excitation button, use the battery to magnetize it;

3) With a bulb load, run for a few seconds at overspeed.


Diesel generator maintenance procedure:

Level A maintenance I

Daily: 1) Check daily work report of diesel generator set. 2) Check the generator: oil level, coolant level. 3) Daily check whether the generator is damaged, mixed with leakage, and whether the belt is loose or worn. 2、 Weekly: 1) Repeat daily Level A inspection. 2) Check the air filter, clean or replace the air filter core. 3) Drain the water or sediment from the fuel tank and fuel filter. 4) Check the water filter. 5) Check the starting battery. 6) Start the generator and check for effects. 7) Clean the front and rear fins of the cooler with an air gun and clean water.

Level B maintenance

1) Repeat Level A daily and weekly inspections. 2) Replace the generator oil. (The oil change interval is 250 hours or one month) 3) Change the oil filter. (The replacement interval of the oil filter element is 250 hours or one month) 4) Replace the fuel filter element. (The replacement interval is 250 hours or one month) 5) Replace the coolant or check the coolant. (The replacement cycle of the water filter element is 250-300 hours. Fill the cooling system with supplemental coolant DCA) 6) Clean or replace the air filter. (The replacement cycle of the air filter is 500-600 hours) Level C maintenance 1) Replace the diesel filter, oil filter and water filter, and replace the water and oil in the water tank. 2) Adjust the fan belt tension. 3) Check the supercharger. 4) Disassemble, inspect and clean PT pump and actuator. 5) Remove the rocker arm chamber cover, and check the T-shaped pressing plate, valve guide and inlet and outlet valves. 6) Adjust the nozzle lift; Adjust the valve clearance. 7) Check the charging generator. 8) Check radiator of water tank and clean external radiator of water tank. 9) Add water tank to the water tank and clean the inside of the water tank. 10) Check the diesel engine sensor and connecting wire. 11) Check the instrument box of diesel engine. Level D maintenance 1) Replace the oil, diesel, bypass and water filters, and replace the oil and engine circulating water. 2) Clean or replace the air filter. 3) Remove the rocker arm chamber cover and check the valve guide and T-shaped pressing plate. 4) Check and adjust the valve clearance. 5) Replace the upper and lower pads of the rocker arm chamber. 6) Check the fan and bracket, and adjust the belt. 7) Check the supercharger. 8) Check the electrical circuit of the diesel engine. 9) Check the circuit of motor excitation part. 10) Connecting lines in the measuring instrument box. 11) Check the water tank and external cleaning. 12) Repair or replace the water pump. 13) Disassemble and inspect the wear of the main bearing bush and connecting rod bush of cylinder 1. 14) Check or adjust the working condition of electronic speed regulation. 15) Inject lubricating grease at the lubricating point of the generator. 16) Align the excitation part of the generator for dust removal. 17) Check the axial and radial clearance of the supercharger, and timely repair if it is out of tolerance. 18) Clean and calibrate the fuel injection nozzle and fuel pump。