SabunjiuDry ty
SabunjiuAlarm (I) the distance between the external contour of 10kV and below dry-type transformer and the surrounding guardrail or courtyard wall shall take into account the convenience of transportation and repair of dry-type transformer, and the distance shall not be less than 1m; At the angle with actual operation, a spacing of more than 2m shall be reserved; If metal fence is selected, the metal fence shall be grounded and a warning sign shall be hung at a prominent position.
If the above provisions are not met, it is OK to operate the centrifugal fan for a period of time. Check the cleanliness of the power transformer. If too much dust is found, it must be eliminated to ensure indoor ventilation and avoid insulation penetration. In particular,SabunjiuFunction of oil immersed transformer, such as ventilation duct, and there shall be no dirt.
Sabunjiu.Two point grounding device of iron core caused by residual welding scar;
What about oil immersed transformer fire?
.If the power transformer stops running for more than 72h (if the allowable time should be reduced when the ambient humidity is & amp; gt; 95%), it should be insulated before putting into use, and accurately measured with a 2500V grounding megger. The insulation resistance from the primary side to the secondary side and the ground should be ^ 300mfl, the insulation resistance from the secondary side to the ground should be ^ 100mh and the insulation resistance from the iron core to the ground should be & amp; gt; 5mfl (note that the grounding device piece should be removed).
Overload or short circuit occurs inside the power transformer. Flammable insulating raw materials are endangered by high temperature and electric isolation, which dissolve and ignite, resulting in a lot of steam bodies, greatly increasing the internal working pressure of the power transformer, causing the ignition of the casing, causing large-scale power failure, endangering all normal production, manufacturing and activities. There are three reasons for fire accidents in the operation of power transformers.
A zero line of the power transformer is connected with the working equipment. Since the voltage formed by the server during operation will be sent to the power transformer along with the cable, the power transformer will be transported and sent to the power consuming machines and equipment. What is the zero line of the actual power transformer? Let's introduce it to us.
The zero line is mainly used in the working circuit. The voltage caused by the zero line is equivalent to the line resistance multiplied by the current of the working circuit. Because of the distance, the voltage caused by the zero line can not be ignored. As a countermeasure to maintain life safety, it is more and more unreliable. Ground wire (PE): it is not used as a working circuit, but only as a maintenance line. Use the affirmation of the earth & ldquo; 0” Voltage. When the machine and equipment casing is electrified the current will be quickly grounded. Even if there is a lead for the PE line, it will be grounded from the surrounding grounding body.
Overtemperature alarm and trip: collect winding or iron core temperature data signals according to the temperature measurement resistor of PTC discrete system thermistor embedded in the bottom voltage winding. When the transformer winding temperature rises again, if it reaches 155 ℃, the system software outputs the overtemperature alarm system; If the temperature rises to 170 ℃ again and the transformer can no longer operate, the overtemperature trip data signal must be transported to the secondary maintenance circuit, and the transformer shall be tripped quickly.
In fact, ground wire is not only a kind of grounding protection. The following describes in detail that ground wire is the general name of grounding system. Ground wire is divided into protective grounding and safety factor grounding device. Among them, safety factor grounding device can be divided into grounding protection, anti electric shock grounding device and anti electromagnetic wave radiation grounding device. Protective grounding is to use it for loop to make the facilities achieve the grounding wire specified by the function.
reform.Equipped with a temperature controller, platinum thermistor (pt10) is placed beside the embedded hole on the top of the low-voltage solenoid coil to test the winding resistance temperature rise of the transformer, stop the cooling centrifugal fan, set up common problem alarm, overtemperature alarm and overtemperature tripping effect, and provide reliable overvoltage protection machinery and equipment for the dry test transformer, so as to test the safety performance of the transformer operation.
Operation of oil immersed transformer
The technical specification of power consumption requires that the resistance of maintenance grounding wire shall be ≤ 4Ω,SabunjiuCan oil immersed transformers be located underground, The resistor is generally more than 2000 & omega;, when the insulating layer is damaged, the current is only 1 / 500 of the total current flow so as to play a guarantee effect. The higher the voltage,SabunjiuLatest model of oil immersed transformer, the smaller the resistance, in other words, in the case of high voltage. We can care about the power transformer plant and master a lot of professional knowledge.
In relay protection dry-type transformer, the disconnection of the fault point is related to each other. In a word, if there is any problem at a certain point, it will affect the whole power circuit
Honest service.It is generally made due to unreasonable installation or ineffective sealing. Polymer composite materials can bond metal materials, porcelain, laminated glass and other materials very well, so as to achieve the pressure management of oil leakage.
The proper selection of Anhui dry-type transformer has a key effect on improving the safety and smooth operation of power system software. In the above original text, we have already mastered the structure and characteristics of dry-type transformer. In this part, we will describe how to select dry-type transformer according to the load characteristics and application environment of dry-type transformer.
Oil leakage at looper flange
Sabunjiu.When the new oil filled by the power transformer and the oil sample that has just been considered are used, the oil sample can be used only after sufficient standing.
It will also produce many faults, effectively deal with various faults of oil immersed transformer, and continuously improve the safety factor of oil immersed transformer. Ignition is a common fault of oil immersed transformer. The key fault of oil immersed transformer is short-circuit fault, and short-circuit fault is more general.
The heat discharge pipe of heat pipe radiator is generally made of slotted seamless steel pipe after flattening by stamping die. When the heat discharge pipe is bent and welded by electric welding, oil leakage is often caused. This is due to the supporting force on the surface of the pipe and the working pressure on the inner cavity when stamping the heat discharge pipe.