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, and overload is not allowed in the whole process of operation.
Therefore, in the installation process of substation equipment, the lightning rod should be set according to the specific situation to prevent damage to the relay protection dry-type transformer caused by lightning. In addition, in the installation and use process of lightning rod, select reasonable types of lightning rod according to the operation situation to determine that they are in the same situation. In addition, during the installation of lightning rod, please connect all routes as far as possible to prevent other faults.
Esperanto.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, cracking, loosening, ignition smoke, oil leakage, broken strand disconnection, hanging of dirty things etching and turbidity, which can be inspected according to the visual inspection method. Therefore, visual inspection is one of the common methods of equipment inspection.
Before application, the sampling container shall be cleaned with vehicle gasoline, soapy water or other organic solvents (such as trisodium phosphate) except oil stains, and then washed with tap water until it is not alkaline, and the water can be evenly distributed from the bottle, and then cleaned with purified water for many times. The cleaned sampling container shall be dried in a 105 ℃ drying oven. After refrigeration, the bottle cap shall be tightly closed and cannot be opened before application.
.What about oil immersed transformer fire?
Before application, the sampling container shall be cleaned with vehicle gasoline, soapy water or other organic solvents (such as trisodium phosphate) except oil stains, and then washed with tap water until it is not alkaline, and then cleaned with purified water for many times. The cleaned sampling container shall be dried in a 105 ℃ drying oven. After refrigeration, the bottle cap shall be tightly closed and cannot be opened before application.
Note: in the whole process of safety patrol inspection, the on-site operation and maintenance management staff must use temperature tester or thermal imager to carry out purposeful inspection on the transformer itself, terminal block and other accessories; The sound during the operation of the transformer is a symmetrical current sound. If the sound is found to be abnormal, or there is local sound, the cause shall be found immediately and certain effective measures shall be taken. If necessary, the load can be reduced or the operation of the transformer can be stopped.
Causes of fire in power transformer
Under normal conditions, different oil-based oils cannot be mixed. Under special circumstances if it is necessary to use new oil of different grades, it should be determined whether the mixed oil with ice degree can be used according to the requirements of the region, and then the oil mixing test should be carried out.
Sound in case of phase failure
Administration.Fault judgment of power transformer
There are many connection groups of dry-type transformers, and the selected structures and connections are also different. Then, what are the groups of dry-type transformers? How to carry out the connection? Or basically introduce it with the network of dry-type transformer manufacturers.
The dry-type transformer is composed of two winding resistances, resulting in four wiring groups: & ldquo; y, Y & rdquo;, & ldquo; D, Y & rdquo;, & ldquo; y,EsperantoMarket price of scb11 dry type transformer, D & rdquo; and & ldquo; D D & rdquo;. In China, only & ldquo; y, Y & rdquo; and & ldquo; y, D & rdquo; are selected. Because there are also two types of Y-connection with neutral line and without neutral line. If there is no neutral line, it will not be upgraded. All marks show that with neutral line, it will not be upgraded The letter N after the English letter Y indicates that the neutral line has transformer grounding wire. Yn0 wiring group, when UAB and UAB overlap, the minute hand points to 12. & ldquo; 12 & rdquo; in the new wiring group, it is indicated by & ldquo; 0 & rdquo.
The sampling container is a colorless glass bottle with a wide mouth ground glass plug with a volume of 0.5kg or 1kg. 2-3 bottles shall be collected at a time for analysis and experiment. Labels shall be attached during sampling. Pay attention to the name source, sampling date, sampling person, weather conditions and other materials of the oil sample.
retailer.The insulating layer in the middle of the silicon steel plate is aging, the anchor bolt cover with the iron core is damaged, the iron core causes large vortex, temperature rise, and the aging of the insulating layer is accelerated. The core insulation compressive strength of power transformer must be measured on time and accurately. If it is found that the insulation compressive strength is less than the index value, please remove and replace the anchor bolt cover or carry out insulation for the copper core cable.
Several detection methods for installing transformer
The oil in the machinery and equipment of the oil storage tank shall generally stand for more than 8h before sampling; it is not necessary to stand when sampling on the running power transformer.
Esperanto.For the installation of lightning rod, it is very easy to damage the relay protection inside and outside of dry-type transformer by lightning. If it is a serious situation, it is very easy to cause fire accidents, power failure, damage to machinery and equipment, etc.
For no-load impulse closing of transformer, pay attention to the following matters:
Oil leakage at electric welding position