Diesel Generator Set: 38 Common Questions
1, the impact of different climatic environments on the operation of diesel generators:
rainwater
Dust and sand
Salt water and fog by the sea
The air contains corrosive gases such as sulfur dioxide
2, the composition of diesel generator set:
Diesel engine, generator, controller. Other components: base, base oil tank, radiator, water tank, recoil pad, anti-sound box, silencer, static speaker and other components.
3, diesel generator set three filter replacement time is how long:
Air filter: 1000 hours, can be more different environment to shorten the replacement cycle.
Diesel filter: The first work is 50 hours to replace, after which it is generally 400 hours to replace. If user
The quality of diesel used is not good, and the replacement cycle should be shortened.
Oil filter: the first work 50 hours to replace, after the general is 200 hours to replace.
4.How to identify the authenticity of the engine:
Appearance: For professionals who are familiar with the engine, the appearance, color,
Overall color difference to identify the authenticity of the engine.
Identification: The body of the diesel engine has the corresponding brand logo label.
Nameplate resolution: the nameplate on the engine has the engine number, the cylinder block, the oil pump also has the corresponding code, call the original factory to confirm the code, you can know the authenticity of the power.
5, motor protection level IP introduction:
I represents the level to prevent the entry of solid foreign objects, the highest level is 6;
P stands for water protection level, the highest level is 8.
For example, protection level IP56, IP55, etc. (Protection level of D.J Power generator is IP56)
6, motor insulation grade introduction:
The insulation grade of the motor is divided according to the heat resistance grade of the insulation material used, which is generally divided into 5 levels:
Class A 105 degrees
Class E 120 degrees
Class B 130 degrees
Grade F 155 degrees
H-class 180 degrees
The D.N Power generator has an H class theater rating.
7, noise level introduction:
30 ~ 40 decibels is the ideal quiet environment. Anything above 50 decibels can interfere with sleep and rest. Above 70 decibels will interfere with conversation and affect work efficiency. Living in a noise environment above 90 decibels for a long time will seriously affect hearing and cause diseases such as neurasthenia, headache, and elevated blood pressure. If suddenly exposed to a noise environment of up to 150 decibels, the auditory organs will suffer rapid trauma, causing the rupture of the eardrum and bleeding, and the complete loss of hearing in both ears. In order to protect hearing, the noise should be controlled not to exceed 90 decibels; In order to ensure work and study, the noise should be controlled not more than 70 decibels. In order to ensure rest and sleep, the noise should be controlled not more than 50 decibels.
8. The purpose of parallel operation of diesel generator sets;
Expansion of power supply capacity
Improve power supply reliability and realize uninterrupted power supply.
9. ATS Functions:
ATS is a switch between the mains power supply and the power generation power supply two groups of switching contacts, one group is used for power generation, the other group is used
On the mains. Automatic switching can be achieved through the controller instruction.
10. Fuel consumption calculation:
Fuel consumption (L/h) = diesel engine rated power (kw) X fuel consumption rate (g/kwh) / 1000/0.84
(The density of diesel 0# is 0.84kg/L)
11, diesel generator set commissioning steps:
Diesel engine inspection -- generator inspection -- no-load commissioning -- on-load commissioning -- Fill in the commissioning report -- clean the site
12, the generator set can be divided into several categories from energy:
Nuclear, hydro, wind, fire. Which fire is divided into coal, diesel, gasoline, gas, biogas. The generators we operate now are mainly diesel generators. Diesel is divided into light diesel (0# diesel, often used in high-speed diesel engines) and heavy oil (120#, 180# diesel, often used in medium-speed diesel engines and low-speed diesel engines).
13. Main functions of the control system:
With manual, automatic, test stop
It has various safety protection functions
Memory of various faults in operation
LED fault display alarm
Display voltage, current, frequency, etc
An external computer can be connected, but requires the controller to have RS232, 485 ports
14, diesel generator group time overload how:
The unit usually cannot be overloaded during operation, but can withstand short-term overload. If the unit overload time is too long (super
Overrated power) Something may happen.
Includes:
Cooling system overheating
Generator winding overheating
Low oil pressure due to decomposition of lubricating oil concentration
Unit life is shortened
15, what happens if the unit load is too low?
If the unit is operated at low load for a long time, the water temperature will rise less than the normal temperature, the viscosity of the oil will be large, and the friction will be larger. The oil that should be burning in the cylinder is heated and causes a paint surface to form on the cylinder gasket. If the low load continues, blue smoke may appear, or the surface paint of the cylinder pad may need to be removed, or the cylinder pad may need to be replaced.
16. What do you need to pay attention to when installing the exhaust system?
The generator set has its standard configuration, such as industrial mufflers, flexible exhaust connections, elbows. The user uses what is provided
Auxiliary facilities can be installed exhaust system. However, the following points need to be noted during installation:
1. Make sure the back pressure is lower than the set maximum (usually, no less than 5Kpa)
2. Fixed exhaust system to avoid transverse and longitudinal pressure.
3. Leave room for contraction and expansion
4. Leave room for vibration
5. Reduce exhaust noise
17. Is it feasible to add cooling water immediately when the diesel engine temperature is too high?
Absolutely not, wait until the engine naturally cools to room temperature before adding cooling water. If the diesel engine is short of water and overheating
The sudden addition of cooling water under the situation will cause cracks in the cylinder head, cylinder liner, cylinder body, etc. due to drastic changes in cold and heat.
Cause serious damage to the engine.
18. ATS self-switching procedure:
1. Module manual operation mode:
After opening the power key, press the "manual" button of the module to start directly. When the unit is successfully started and normal operation, at the same time, the automation module also enters the self-test state, which will automatically enter the speed up state. After the successful speed up, the unit will enter the automatic closing and grid connection according to the display of the module.
2. Automatic operation mode:
The module is set in the "automatic" position, the unit enters the quasi-start state, in the automatic state, through the external switch signal, the mains state automatic long-term detection and discrimination. Once the mains failure, power loss, immediately enter the automatic start state. When the mains power is called, it will automatically switch the switch switch and reduce the speed to stop. When the mains is restored to normal, the system confirms that the unit automatically trips out of the network, delays for 3 minutes, automatically stops, and automatically enters the next automatic start ready state.
19, diesel generator set cylinder seal is low bad start how to do?
When the engine is cold started, especially in winter, because there is very little oil on the piston ring and cylinder wall, the sealing effect is not good, and the phenomenon of repeatedly starting and not running on fire will occur. The diesel generator set sometimes seriously affects the sealing performance of the cylinder due to heavy cylinder wear, making it more difficult to start. In this regard, the injector can be removed and 30 to 40ml of oil can be added to each cylinder to enhance the sealing performance of the cylinder and improve the pressure during compression.
20, diesel generator self, protection function.
Diesel engines and alternators are installed with a variety of sensors, such as water temperature sensors, oil pressure sensors, etc., through these sensors, the intuitive running status of the diesel engine is displayed to the operator, and with these sensors, you can set an upper limit, when the limit value is reached or exceeded when the control system will alarm in advance. At this time, if the operator does not take measures, the control system will automatically stop the unit, and the diesel generator set is self-protecting in this way.
The sensor plays the role of receiving and feedback various information, and it is the control system of the diesel generator set that really displays these data and performs the protection function.
21. What are the noise sources of diesel generator sets?
Intake noise, exhaust noise and cooling fan noise
Combustion noise of combustion chamber operation, mechanical noise of engine parts friction
Noise generated by rotor rotating at high speed in electromagnetic field
22, winter diesel generator starting skills.
Preheating: The cooling system can heat water and heat the oil pan with a heat source.
Improve air tightness: the injector can be removed and 30 ~ 40ml oil can be added to each cylinder to enhance the sealing performance of the cylinder and improve the pressure during compression.
Turning: Shake the crankshaft before starting to make it run easily and then start.
23. What is the role of the piston ring of the diesel generator set?
Heat transfer
Control oil
Supporting effect
Keep air tight
24, the new machine running-in several ways and sequence?
First cold running-in, manual rotation, or external force to drive the crankshaft rotation.
After hot running, no load running.
25, the cause of oil deterioration?
Use the wrong oil grade and substandard oil.
The operation condition of the unit is not good, gas channeling, oil channeling, cooperation gap is too large, oil temperature is too high.
Units often operate at low temperatures.
Exhaust gases enter the oil pan and condense into moisture and acid.
The oil filter is too dirty, the filter leaks, and the oil is not filtered by the filter.
26, the role of oil pump?
The function of the oil pump is to give the lubrication system enough pressure of the oil, so that each mutual movement of the parts are effectively lubricated, and the gear type and rotor type oil pump are widely used on the diesel engine.
27, what is the role of the governor?
The governor should be able to adjust the fuel supply sensitively according to the changes in the external load to maintain the stability of the speed. It must have two basic parts: the induction element and the actuator.
28, the function of the automatic regulator?
The automatic voltage regulator (AVR) tightly maintains a stable voltage from no load to full load. The AVR has a voltage frequency (Hz) proportional feature, which allows the output voltage to be adjusted correctly when the rated speed is reduced. This feature helps to protect the engine when a large load is suddenly added.
29, battery maintenance?
For frequently used machines, the battery is generally not a problem, as long as the maintenance policy is good, if the battery has not been used for a long time, it is necessary to regularly check its power and charge it, every 12 weeks (8 weeks in the tropics).
30. Under what circumstances does the unit automatically delay shutdown?
The fuel level is too low, the water temperature is too high, the water level is too low, the load is too high, the start fails, and sends the corresponding signal.
31, the unit in what situation emergency shutdown?
Overspeed, short circuit, phase loss, high voltage, voltage loss, low frequency
32. Under what circumstances does the unit automatically issue an audible and visual alarm signal?
Oil pressure is too low, water temperature is too high, water level is too low, overload, starting failure, overspeed, short circuit, phase loss, voltage is too high, voltage loss, low frequency, starting battery voltage is too low, starting battery voltage is too high, low oil level and the alarm system of the unit has relay contacts.
33, the type of oil filter of diesel generator set?
Mechanical separation
Centrifugal separation
Magnetic adsorption
34, compression ratio becomes smaller what is the reason?
The position of the piston at the end of compression is low: the relevant parts wear, deformation, etc.
Combustion chamber volume increases: valve seat ring wear, piston top sag, cylinder pad is too thick.
35. What are the automatic control functions of diesel generator sets?
Automatic heating device
Automatic adjustment of diesel engine speed
Charging system
Instrument system self
Protective device
Starting system
36. How does the automatic heating device work?
On the diesel engine, the cooling water automatic heating device is generally installed to make the generator set in the standby state, the diesel engine should be in the heat engine state, so that the generator set will start the generator set and work with load within 15s when the mains power is lost.
Diesel engine automatic heating device, when the water temperature is below 30 degrees Celsius, the thermostat contact is connected, KM suction, and the heater EH works. When the water temperature rises to 50 degrees Celsius, the thermostat contact is disconnected, KM is released, and the heater EH is powered off.
In addition to the cooling water heating device, there are oil heating devices and battery heaters.
37, how to use the naked eye to observe the power of maintenance-free battery?
There is generally a transparent observation port above the battery, we look down from the top, you can see the color inside, if it is green indicates that the battery is sufficient, if it is white, it indicates that it needs to be charged, if it is black, it indicates that it needs to be replaced.
38, what is the white solid on the battery terminal?
This is a normal phenomenon, the white solid is the product of the oxidation of the battery terminal and the air, and it will disappear when it is cleaned with boiling water.
