Installation place: a place without fire, explosion hazard, conductive dust, chemical corrosive gas and severe vibration. If the above conditions are exceeded, the user can negotiate with our company.
Box-type transformers and European-style transformers (usually referred to as "box-type transformers" and "European-type transformers") centrally design traditional transformers in box-type housings, which have small size, light weight, low noise, low loss, and high reliability. They are widely used in Urban power grid reconstruction, residential quarters, high-rise buildings, industrial and mining, hotels, shopping malls, airports, railways, oil fields, docks, expressways, commercial centers, light stations, factories and mines, enterprises, hospitals, schools, etc. , Outside places.
Chinese name: Box type transformer (European type transformer)
Form: Fully sealed steel construction
Should apply: Power engineering construction
Principle
As a complete set of power distribution equipment, the box-type transformer is an organic combination of power transformers, high-voltage voltage control equipment, and low-voltage voltage control equipment. The basic principle is to carry out reasonable assembly in accordance with the prescribed order through the pressure starting system, armored line, substation automatic system, DC system and corresponding technical equipment, and install all components in a specific waterproof, dustproof and rodent-proof A specific transformer formed in a fully sealed tempered box structure. Box-type transformers have been widely used in power engineering construction.
Advantage
Because box-type transformers have many advantages such as small footprint, convenient operation, high application benefits, flexible combination methods, and high operational safety, they are widely used in various fields and become an indispensable part of power engineering construction today. important electrical equipment. The advantages are as follows:
First, because the internal structure of the box-type transformer is relatively reasonable, it occupies less space. Compared with traditional transformers, box-type transformers install high-voltage power distribution equipment in a sealed steel structure box through scientific and reasonable means. The transformer also takes up relatively little space.
Second, the operation method of the box-type transformer is very simple and convenient, and it is convenient for quick assembly. Based on the understanding of the construction requirements of electric power engineering, specialized designers make simple and convenient separate main wiring and supporting equipment outside the box according to different requirements, which is convenient for rapid assembly.
Third, the combination of box-type transformers is flexible. Because the box-type transformer has the characteristics of compact and simple structure, each of its monomers is an independent system, which makes the box-type transformer quite flexible in the way of combination.
Fourth, the safety and stability of box-type transformer operation are high. Because the shell of the box-type transformer is made of a metal conductor with strong anti-corrosion ability, and the interface between the internal equipment and the equipment is also made of insulating materials. The box is equipped with air conditioning and moisture removal equipment, which greatly improves the box-type transformer. The resistance of the transformer to the external environment improves the safety and reliability of its operation.
Equipment structure
The box-type transformer is not just a transformer, it is equivalent to a small substation, which belongs to the distribution station and directly provides power to users. Including high-voltage room, transformer room, and low-voltage room; the high-voltage room is the incoming power supply side, including high-voltage busbars, circuit breakers or fuses, voltage transformers, metering devices, lightning arresters, etc. There are low-voltage busbars, low-voltage circuit breakers, metering devices, lightning arresters, etc. in the low-voltage room, and the lines drawn from the low-voltage busbars supply power to users.
Machine maintenance
1. Disconnect the circuit breaker on the low-voltage side of the box-type transformer for maintenance, remove the operation insurance of the control power supply, and hang the "no closing" sign on the switch handle.
2. Disconnect the circuit breaker on the high-voltage side of the maintenance transformer, close the grounding switch, and after fully discharging the transformer, lock the high-voltage cabinet, and hang the "no closing" sign on the switch handle.
3. For the maintenance of box-type transformers, first clean the porcelain bushing and casing, and then check whether the casing, gasket, and porcelain casing are cracked, whether there are discharge traces or aging of the rubber pad, whether there is any deformation of the cable and busbar, and whether there is any crack. Should be replaced.
4. Check whether the contact surface of the busbar is kept clean. The oxide layer should be removed and coated with electric compound grease.
5. Check whether the grounding of the transformer is good, whether the ground wire is corroded, and replace it if it is severely corroded.
6. Tighten the lead terminals, pins, grounding screws, and connecting busbar screws. If there are any loose screws, remove the screws, or use a fine flat file to lightly file the contact surface, or replace the spring washers and screws until the contact is good.
7. Clean the dust around the transformer and accessories, and check whether the fire-fighting facilities and ventilation system are in good condition.
8. Disconnect the grounding switch on the high-voltage side, lock the high-voltage switch bar, and measure the insulation resistance with a 2500V shaker. And compared with the measured value of the transformer before leaving the factory, the insulation resistance should not be lower than 70% of the original data at the time of delivery. If it is unqualified, it should be reported and dealt with in time.
9. Close the grounding switch on the high voltage side again to let the transformer discharge.
10. Check the transformer room and transformer for leftover tools, and evacuate the site.
11. Connect the low-voltage side circuit breaker to control the power supply operation insurance, and re-hang the "no closing" sign to prevent reverse power transmission to the transformer.
12. Disconnect the grounding switch on the high-voltage side, check the transformer site and the control line on the low-voltage side again, and after it is correct, close the circuit breaker on the high-voltage side of the transformer, let the transformer run for trial operation, and remove the signboard on the high-voltage side.
13. Make a detailed record of maintenance and trial operation.