Commissioning of diesel generators

Before the diesel generator set is installed, it must be fully inspected before being put into operation.

Unpacking of the diesel engine To prevent diesel engine corrosion, when the product leaves the factory, both the inside and the outside are oil-sealed. Therefore, after the new unit is installed and meets the installation requirements, it must be unsealed before it can be started. Whether it will cause danger of speeding should be taken seriously.

The steps to remove the oil seal are as follows:

(1) The diesel oil is heated to 45 ° C ~ 56 ° C for washing and erasing the external antirust oil.

(2) The water is heated above 90 ° C, and then is continuously filled from the water outlet of the water jacket, and flows out from the water release switch (or the water inlet of the pump) on the side of the cylinder body for 2 to 3 hours continuously, and the crankshaft is intermittently rotated , Dissolve the rust-proof oil on the piston crown, the surface of the cylinder liner and other places.

 (3) Clean the oil pan with clean diesel oil and change into new oil. Cooling and fuel systems, fuel injection speed control systems, water pumps, and start-up transmission systems should be cleaned and inspected in accordance with the instructions, and sufficient cooling water should be added to fully start the battery and make preparations before starting.

◎ Inspection before unit test

(1) The inspection steps before the diesel engine is tested as follows:

1) Check whether the surface of the unit is clean; whether the ground nuts, flywheel screws and other moving parts are loose or not, tighten them if you find any problems.

2) Check whether the clearance of each part is correct, especially check the clearance of the inlet and exhaust valves and the clearance of the decompression mechanism to meet the requirements.

3) Put each cylinder in the decompression position, turn the crankshaft to check whether there is any abnormal sound of the operating sound of each cylinder's parts, and whether the crankshaft can rotate freely. At the same time, pump the oil into a friction surface, then close the decompression mechanism and shake the crankshaft Check the cylinder for air leakage. If you shake the crankshaft, it feels very laborious, indicating that the compression is normal.

4) Check the condition of the fuel supply system. The steps are as follows:

① Check if the vent hole on the fuel tank cover is smooth. If there is any dirt in the hole, it should be removed. Whether the added diesel meets the required grade, whether the fuel quantity is sufficient, and turn on the oil circuit switch.

② Turn on the decompression mechanism and crank the crankshaft. Each cylinder should have a crisp injection sound, which indicates that the injection is good. If the sound of fuel injection does not come, there may be air in the oil circuit. At this time, you can loosen the air filter screw of the diesel filter and the fuel injection pump to remove air in the oil circuit.

③ Inspect the oil pipes and joints for oil leakage, and solve the problems in time.

5) Check the condition of the water cooling system, the steps are as follows:

① Check whether the amount of cooling water in the water tank is sufficient. If the amount of water is insufficient, clean soft water should be added.

② Check whether there is water leakage in the joint water pipe and solve the problem in time.

③ Check whether the impeller of the cooling water pump rotates flexibly and whether the transmission belt is tight. Check the tightness of the transmission belt, and push it by hand in the middle of the rotating belt.

 6) Check the condition of the lubrication system, the steps are as follows:

① Inspect the oil pipe and pipe joints for oil leakage, and solve the problem in time.

② Check the amount of oil in the oil pan, pull out the dipstick next to the crankcase, and observe whether the height of the oil level meets the requirements of the rules. Otherwise, add engine oil. For diesel engines, add No. 8 or No. 11 diesel engine oil in winter and summer. 14th motor oil.

In the inspection, if the oil level is found to be above the regulation height, the reason for the increase in engine oil should be carefully analyzed. There are usually three reasons. a. When adding oil, add too much. b. Diesel leaks into the crankcase and thins the engine oil. c. Cooling water leaks into the oil. ③ For oil holes that require manual refueling, all oil should be filled with grease for grease gun.

7) Check the condition of the starting system, the steps are as follows:

① Start the diesel unit with a point. The steps are a. First, check whether the electro-hydraulic specific gravity of the starting battery is in the range of 1.240 ~ 1.280. If the specific gravity is less than 1.180, the battery power is insufficient. b. Check if the power cord is correct. c. Check the battery terminals for dirt or oxidation. Polish them. d. Check whether the electric contact of starting motor and electromagnetic control mechanism is good.

 The alternator installation inspection steps are as follows:

1) The alternator and diesel generator are coupled, and the parallelism and concentricity of the coupling are required to be less than 0.05mm. In actual use, the requirements can be slightly lower, about 0.1mm, too large will affect the normal operation of the bearing, resulting in damage, coupling must be fixed with a positioning pin. Check the coupling before installation.

2) When the generator with sliding bearing is coupled, the height of the generator center should be adjusted slightly to the center of your diesel engine, so that the weight of the flywheel on the diesel engine will not be transferred to the generator bearing, otherwise the generator bearing will bear extra The weight of the flywheel is not conducive to the formation of the oil film of the sliding bearing, which causes heat generation and even burns the bearing. Do not carry any heavy objects on the coupling of this type of generator.

3) When installing the generator, ensure that the cooling air inlet is unobstructed, and avoid the hot air from entering the generator. If there are shutters on the ventilation cover, the window should face down to meet the requirements of the degree of protection.

 4) The mechanical coupling of single-bearing generators must pay special attention to the uniform air gap between the stator and rotor.

5) According to the schematic diagram or wiring diagram, select the appropriate power cable and use copper connectors to connect the copper connector and the busbar. After the busbar and the busbar are firmly fixed, the local gap at the joint is not greater than 0.05mm, and the distance between the wires No more than 10mm, the necessary grounding wire must be installed.

6) The U, V, W, N marks are printed on the terminals of the generator outlet box. He does not indicate that the actual phase sequence depends on the direction of rotation. The UVW printed on the certificate indicates the actual phase sequence when rotating clockwise, and the VUW indicates the actual phase sequence when rotating counterclockwise.

 7) If the neutral points of each generator in the power supply system are connected to each other, or when the generator neutral point is connected to the transformer and its load neutral point, the unit will run on the neutral line at a frequency of 3 times the neutral line Current. Therefore, the neutral current of the generator must be measured under various load conditions that may occur during operation. In order to prevent the generator from overheating, the line current must not exceed 50% of the rated current of the generator. Neutral line power is too large, and a neutral line reactor should be installed on the neutral line to limit it