`IBRICharacter
SuharDry type 
SalaraDry typeThe flange surface is uneven, the tightening bolts are loose, and the installation and processing process is wrong, so that the bolts are not tightened well, resulting in oil leakage.
The technical specification of power consumption requires that the resistance of maintenance grounding wire shall be ≤ 4Ω, The resistor is generally more than 2000 & omega;, According to Ohm's law, 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, 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.
Ghis Rabat.The common dry-type transformer is an important electrical equipment, and the voltage is constantly regulated. However, because of certain necessity, the dry-type transformer will also boost voltage, and the whole process of boosting voltage is very complex, and there are many principles.
If the above provisions are not met, the problem of dryness shall be solved. Generally, 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 pay attention to cleaning the insulators of the power transformer and the top and bottom ends of winding resistance installation. Portable centrifugal fan or dry air compression or N2 shall be used to clean the dust in indoor space that is not easy to reach, such as ventilation duct, and there shall be no dirt.
.The switching power supply lacks one phase of power;
The long-term overload of power transformer will slowly cause the scalding and insulation aging of solenoid coil, resulting in short circuit between coils, two-color short circuit or short circuit on the ground, resulting in the ignition of power transformer. Therefore the insulation compressive strength of power transformer shall be tested before installation and operation, the winding of oil immersed transformer is generally divided into multiple modules, and each module is replaced by an equivalent circuit, and its power circuit includes an inductance and vertical capacitance, a capacitance to ground or capacitance between windings, They also have mutual inductors between the inductors of each module, and collect the chain Internet as the equivalent power circuit of oil immersed transformer. The precision of the conclusion can completely meet the needs of practical projects.
The visual inspection method is that the staff use human eyes to observe the appearance change of the visible parts of the operating equipment to find the abnormal conditions of the equipment, such as discoloration, deformation, offset,Ghis RabatDry type transformer, cracking, loosening, oil leakage, broken strand disconnection, short-circuit fault marks, hanging of dirty things, etching and turbidity, which can be inspected according to the visual inspection method. Therefore,Ghis RabatProduction process of oil immersed transformer, visual inspection is one of the common methods of equipment inspection.
When sampling from a small and medium-sized power transformer without a discharge pipe (or oil sample suspension plate), it can be in a power transformer such as a glass test tube when it is not in operation to extract the oil sample at the bottom, or it can be replaced by changing the oil.
Quality department.Loose core screw
When oil samples are used, the safety and fire safety technical specifications on the spot shall be strictly implemented.
The raw materials of Fushi blue can be used for bonding, so that the overall oil leakage of the connector can be greatly controlled; If the actual operation is convenient, the metal shell can also be bonded at the same time to achieve the purpose of leakage treatment.
The main reason is that the welding quality of electric welding is poor there are empty welding, open welding, needle holes, sand holes and other shortcomings in welding. The oil transformer is easy to be covered with welding powder and paint when leaving the factory, the electromagnetic induction vibration will crack the electric welding and lead to leakage.
market.The capacity and working voltage are different. The dry-type transformer is generally suitable for distribution equipment. The capacity is generally below 2000kVA and the working voltage is below 35KV, which also ensures the rated voltage of 110kV; Oil immersed transformers are generally suitable for distribution equipment.
Protection mode for type selection of dry-type test transformer
When the manufacturer of the power transformer samples from the automobile oil tank, use the cleaned and dried rubber stopper to the oil. At the same time, clamp the branch pipe with your thumb, and loosen your thumb to make the oil enter the pipe,
Ghis Rabat.& ldquo; YN, D11 & rdquo;, in which 11 indicates that when the working voltage phasor of the primary side line, as the minute hand refers to the position at 12 o'clock, the phase voltage phasor of the secondary side is at 11 o'clock. That is, the phase voltage UAB of the secondary side lags 30 degrees behind the working voltage uab330 of the primary side line (or 30 degrees ahead).
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,Ghis RabatTransformer three-phase transformer, 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.
Oil immersed transformer operation