As electricity becomes more and more important to our lives, diesel generators, as independent power generation equipment, provide emergency power in the event of a power failure. Therefore, diesel generators are available in many places. How to properly maintain them when not in use? Next, Xinshengan Power will give you an introduction.As a matter of fact, most of the time the unit is in standby mode, and there are relatively few opportunities to actually put it into use. Usually, it is mostly based on test machines and lacks more complete inspection and maintenance methods. But this kind of emergency backup power is indispensable. How to ensure that the generator can be powered in time in an emergency when the generator is used less often, and the operation is safe and reliable, and it can be shut down immediately after the power failure.Look at the following related diesel generator inspection and maintenance steps.The first step is to check the battery packSince the backup power supply is not often put into use, the key to whether the generator can start normally lies in the maintenance of the battery. If there is a problem with the battery pack, the more common situation is: there is voltage and no current. At this time, you can hear the sound of the solenoid valve in the starter motor, but the coupling cannot be moved.There are three reasons why the battery pack cannot stop due to problems:1. Using the method of stopping charging the battery during the test machine will result in insufficient battery power.2. The mechanical oil pump is driven by a belt, and the pump oil volume at the rated speed is very large. However, the battery pack is insufficiently powered, which causes the spring plate in the shutoff valve to be blocked due to insufficient suction of the solenoid valve to spray from the four oil outlets when the machine is stopped. The fuel can not be shut down.3. Domestic batteries usually have a life span of two to three years and are not replaced regularly.The second step is to check the start solenoid valveWhen the generator is running, people have summed up a set of inspection methods of "one look, two listen, three touch, and four smell". Listening at startup is a very important step. Take the Cummins generator set as an example. Just press the start button and it will start after three seconds. Within these three seconds, two "clicks" can be heard. Once the second sound is not heard, check whether the start solenoid valve is working properly. If the solenoid is blown out, the generator will of course not start.Third, the inspection of diesel oil, lubricating oil and antifreezeBecause the generator set is in a static state for a long time, the various materials of the set itself will undergo complex chemical and physical changes with oil, cooling water, diesel, air, etc., which will "discharge" the set. For this reason, attention should be paid to the oil and water problems, and timely Replace or supplement.
The generator set has been used for a long time, and some minor faults are always inevitable. When the engine water temperature is too high, the water tank boiling phenomenon will occur, so what should we do whne this happens? The user can observe the violent water overflow in the radiator or expansion tank. Open the water tank cover to prevent burns. Then when the generator set has the phenomenon of boiling the water tank, we should proceed as follows:1. Don't turn off the engine immediatly, so as not to burn the cylinder bed, pull the cylinder, and cause greater damage to the unit.2. Do not try to open the water tank cover, otherwise it is very likely that hot liquid will spray out and cause burns3. Do not pour cold water on the cylinder block and cylinder head of the diesel engine. This action is likely to cause the cylinder block of the Perkins diesel generator set to burst due to sudden cooling.4. Remove the engine load, let the engine run slowly from medium speed to low speed, and then increase the speed after the standby temperature drops to normal.5. If there is a lack of cooling water, distilled water, purified water and other soft water can be added to prevent the formation of scale and affect heat dissipation.
In the cold winter, the engine is difficult to start. If you add cold water before starting, it is easy to freeze during the water filling process or when the water is not started in time. The water tank and the water inlet pipe are likely to freeze, causing the water to be unable to circulate, or even Crack the water tank. Filling with hot water, on the one hand, can increase the temperature of the generator set for easy starting; on the other hand, it can try to avoid the above freezing phenomenonAntifreeze should be high qualityAt present, the quality of antifreeze on the market is uneven, and many are shoddy. If the antifreeze does not contain preservatives, it will severely corrode engine cylinder heads, water jackets, radiators, water blocking rings, rubber parts and other components. At the same time, a large amount of scale will be generated, which will cause poor engine radiating and cause engine overheating failure. Therefore, products from regular manufacturers must be used.Replenish soft water in timeAfter filling the water tank with antifreeze, if the liquid level of the water tank is found to be lowered, under the premise of ensuring no leakage, only need to fill with clean soft water (distilled water is better), because the generally used glycol type antifreeze has a high boiling point , What evaporates is the water in the antifreeze, no need to replenish the antifreeze, just add soft water. It is worth mentioning that: Never add hard water that has not been softened.Drain antifreeze in time to reduce corrosionWhether it is ordinary antifreeze or long-lasting antifreeze, it should be released in time when the temperature becomes higher, so as to prevent the corrosion of the machine parts. Because the preservatives added to the antifreeze will gradually decrease or become invalid with the extension of use time. What's more, some simply don’t add preservatives, which will have a strong corrosive effect on the parts. Release the antifreeze in time according to the temperature, and after the release of the antifreeze, the cooling pipeline should be thoroughly cleaned.Change the water and clean the pipeline regularlyIt is not recommended to change the cooling water frequently, because the minerals of the cooling water have been precipitated after a period of use. Unless the water is already very dirty, it may block the pipeline and the radiator. Do not replace it easily, because even if the newly replaced cooling water passes through It has been softened, but it still contains certain minerals. These minerals will be deposited on the water jacket and other places to form scale. The more frequently the water is replaced, the more minerals are deposited, the thicker the scale will be. Therefore, it should be based on actual conditions. Change the cooling water regularly. The cooling pipeline should be cleaned during replacement. The cleaning fluid can be prepared with caustic soda, kerosene and water. At the same time, maintain the drain switches, especially before the winter, replace the damaged switches in time. Bolts, sticks, rags, etc. cannot be used as substitutes.
I. Introduction to the protection of biogas generator sets (1) The 400KW biogas generator set has a complete safety control system. It meets the requirements of JB/T9583.1-1999, NYT1223-2006 biogas generator set, and has the following safety protection devices: 1. Low engine oil pressure alarm, stop 2, engine overspeed alarm, stop 3, the engine cold water temperature is high alarm 4. High methane concentration alarm in the engine room 5. High engine cooling water temperature alarm 6, high engine oil temperature alarm 7, Ignition system fire alarm 8. Generator reverse power protection 9, generator undervoltage protection 10, generator overcurrent protection 11. All rotating parts are protected by steel mesh cover as a protective device. (2) Brief introduction of control screen function: 1. The control panel of the biogas generator set is a floor cabinet structure. The intelligent automatic air circuit breaker (AH) is selected, which has automatic over-current protection and reverse power protection. When over-current or reverse power occurs, it can automatically disconnect the main switch and send out an audible and visual alarm signal. The control panel is equipped with controllers, various display instruments, adjustment buttons, unit protection indicators, emergency stop buttons, etc., which are used to control and monitor the working conditions of the generator set. The start of the generator set is manually operated at the side of the machine, and the shutdown can be controlled at the side of the set, or by the emergency stop button on the control panel. 2. The control system is equipped with imported automatic paralleling control module (optional for users), which can automatically monitor and synchronize to meet manual and automatic paralleling. When multiple units are running in parallel, it can realize automatic load distribution function to meet grid and parallel operation Working conditions. The speed of the unit is automatically adjusted by the electronic speed control system, and it can also be adjusted in a small amount through the speed fine-tuning knob on the control panel; the unit voltage is automatically adjusted, and the voltage is adjusted by the voltage setting potentiometer on the control panel. The control panel is equipped with a floating charging device to provide charging power for the battery. II. Description of the grid-connected protection of the Green Ring biogas generator set 1.Short-circuit protection: Use the electromagnetic release of the main circuit low-voltage circuit breaker for short-circuit protection, and the operating current is set to 8-10 times the rated current. 2.Overcurrent protection: Use the delay release of the low-voltage circuit breaker of the main circuit to set it at 1.25 times the rated current of the generator. 3.Under-voltage protection: Install a voltage-loss release on the low-voltage short-circuit device of the main circuit to open the main circuit breaker when the generator voltage is lower than 50%-60% of the rated voltage. 4.Reverse power protection: When reverse power of 5%-15% of rated power occurs during parallel operation, the reverse power protection device opens the main circuit breaker within 10s. 5. Generator thermal protection: When the stator temperature exceeds 145℃, an audible and visual warning signal will be issued, and the main circuit breaker will be opened when the temperature exceeds 155℃. III. Grid-connected biogas generator set (1) The grid connection of generators should meet three conditions: 1. The voltage of the generator to be paralleled is equal to the voltage of the system. 2. The weekly rate of the generator to be paralleled is equal to the weekly rate of the system. 3. The phase angle of the generator to be paralleled is consistent with the phase angle of the system. (two) grid-connected plan Primary system plan (specifically subject to the generator manufacturer's configuration and the primary system design requirements of the electrical industry department) Plan 1: Generator-generator control cabinet-grid-connected protection cabinet-metering and outgoing circuit breaker cabinet- Incorporate into the low-voltage 400V power grid; Option 2: Generator-Generator control cabinet-Metering and outlet circuit breaker cabinet-Step-up transformer (10KV/35KV)-Metering and PT cabinet-Grid-connected protection cabinet-High voltage Isolating switch-power grid; 2. Relay protection configuration plan (specifically subject to the configuration of the generator manufacturer and the relay protection design requirements of the electrical industry department) In addition to the manufacturer’s standard configuration at the outlet of each generator, a relay is installed On the side of the electrical protection cabinet, an independent overcurrent protection device, an overcurrent protection device in the low-voltage direction, and a low-frequency protection are installed; in order to ensure the safe operation of the generator and prevent the system from sending power back to the generator, it must be at the generator outlet Install a reverse power protection device at the place. (Preferably the grid-connected comprehensive protection device commonly used in power systems) (The grid-connected cabinet of the generator is an "ordinary" high-voltage switch cabinet with a built-in circuit breaker. Because it is connected to the generator system and the grid system, it is installed with complete grid-connected protection The device plays the role of generator grid-connected, and is called "grid-connected cabinet"; the special point of this cabinet is that the protection installed is different from other outgoing switch cabinets, and it is generally equipped with directional overcurrent protection and current time limit quick-break protection , Low-voltage and low-cycle oscillating unloading protection, etc.) Conclusion: Optimal option one. IV. Design of external power grid lines The cross-sectional area of the external power grid line is considered according to the maximum load of the plant area and the capacity of the generator assembly. The grid-connected location is the low-voltage side or the high-voltage inlet side of the plant substation. For example: the capacity of the project's generator set is 2X400KW, the maximum load in the biogas station is 120KW, and the transformer type of the station is 400KVA, then the line of the external power grid is based on 2X400KVA, and the selection can be calculated according to the design specification. V. generator configuration requirementsGenerator configuration: biogas engine, Stanford/Siemens generator, public chassis, control panel, radiator, ignition system, mixer, battery pack, control start signal cable, generator starter, battery charging unit, fan cooling system The control unit (including cables within 50 meters), one waste heat boiler, two circulating water pumps, a generator biogas buffer tank and an indoor piping system, generator spare parts and information; 2. Provide two generator control panels One contact cabinet, one dedicated isolation switch cabinet for grid-connected outlets; 3.one control box screen for each of the and 400GF units and one set of automatic grid-connected devices.