OklahomaElectr
OklahomaPower 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, 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.
For 630kVA power engineering transformer, plastic parts are selected in the middle of iron core, clamp and electromagnetic coil to keep the electromagnetic coil in a stable clamping state to reduce noise.
Oklahoma.How to select dry-type transformer
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.
.How much is the power transformer
Before no-load impulse closing,OklahomaFully sealed oil immersed transformer,OklahomaScb10 dry type distribution transformer, the transformer shall be placed for 24h and the rising seat and waterproof sleeve installed with vent plug shall be deflated on time.
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, and the potential safety hazards are exposed after operation. In addition, the electromagnetic induction vibration will crack the electric welding and lead to leakage.
Avoid inadvertent damage of insulation during maintenance: when repairing the hanging core of power transformer, special attention shall be paid to the maintenance of solenoid coil or insulating waterproof sleeve. If there is scratch damage, it shall be handled properly.
The insulation between silicon steel sheets is damaged, resulting in overheating and melting of the iron core;
& ldquo; of wiring transformer; Enter & rdquo; And & ldquo; Output & rdquo; Use a megger to test the grounding resistance between the terminal and the ground wire. When accurately measured by 1000V megger, the resistance value exceeds 2m ohm bus.
system.According to the condition of cracks, galvanized iron wire can be punched into the leakage or riveted with hammer. Then clean the leakage point with toluene and seal it with raw materials. Coated sand casting eyes can be sealed with raw materials immediately.
In terms of the place of use, dry-type transformers are mostly used in & ldquo; Fireproof and explosion-proof type & rdquo; It is easy to use in large and medium-sized engineering buildings and multi-storey buildings; The oil immersed transformer because of & ldquo; Accident & rdquo; There is likely to be oil or leakage after fire, and most application places leading to fire accidents are easy to choose in large and medium-sized engineering buildings and multi-storey buildings;
There are also many problems to pay attention to in the preventive measures and process of dry-type transformer damping. What are the key effects and functions of dry-type transformer damping and the corresponding preventive measures? Let's master and consult in detail with the small editor of the dry-type transformer manufacturer.
In the electric field of the winding to the yoke there must be a strong line breaking component, so that sliding flash charge and discharge may occur at a lower current. In order to better solve this disadvantage, the appearance of the insulating parts between the winding and the iron yoke should be the same as that of the medium horizontal plane of the winding to the iron yoke insulation as far as possible, so as to reduce the electric field component intersecting with the insulating parts.
Promise and keep promise.For the leakage that has already occurred, find the leakage point first, which can not be ignored. For the position with serious leakage, the treatment surface shall be cleaned and tidy. Polymer composite materials are mostly selected for dry consolidation. After dry consolidation, the goal of long-term treatment of leakage can be achieved.
Hand touch method for transformer inspection
Insulation and heat removal are different. Dry type transformers are generally insulated with epoxy resin, cooled by natural air and large capacity by centrifugal fan. Oil immersed transformers are insulated by insulating oil, D11 & rdquo;,OklahomaRated current of 400 KVA dry-type transformer, 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).
Difference between dry-type transformer and oil immersed transformer: