TWSB high voltage test transformer transformer drying method

structure

The iron core of this series of products is a single-phase core type, which is made of high-quality cold-rolled oriented silicon steel sheets, and the fastening method uses steel as a clamp. The high-voltage coil is a cylindrical multi-layer tower type, wound by high-quality polyester enameled wire and high-voltage insulation material. The low voltage coil is outside, and the instrument coil is an independent winding, generally 100V. The shell is octagonal, and test transformers above 10KVA are equipped with movable iron wheels. It has light weight, small size, convenient movement and superior performance.

The working principle of TWSB high voltage test transformer

1. AC, AC and DC test transformers:

Input the power frequency power into the operation box (or console), adjust the voltage through the auto-voltage regulator and input it to the primary winding of the test transformer. According to the principle of electromagnetic induction, power frequency high voltage can be obtained in the secondary (high voltage) winding. After the power frequency high voltage is rectified by the high-voltage silicon stack and capacitor filtering, the DC high voltage can be obtained, and its amplitude is 1.4 times the effective value of the power frequency high voltage. It's just that the short-circuit bar should be drawn out when using DC, and the short-circuit bar should be inserted when using AC.

2. Transformer with tapped test:

In order to satisfy the contradiction between a transformer with a higher voltage and a lower voltage and a lower current and a higher current, the high-voltage winding is divided into two windings, one is the winding with the larger current, the other is the winding with the smaller current, and then Two windings are connected in series and lead out separately, schematic diagram

3. Cascade test transformer:

In order to obtain a higher voltage test transformer, a cascade method can also be used to obtain a higher voltage. Figure 2 shows the principle wiring diagram of a three-stage cascade test transformer. The relationship between the capacity and voltage of the three transformers satisfies: P1=2P2=3P3, U(total)=1U+2U+3U.

characteristics

◆ Data such as voltage, current, time, status information and prompt information are displayed on a 4.7-foot large-screen LCD with clear and intuitive readings;

◆ All Chinese interface, simple and clear operation, can adapt to a variety of applications;

◆ Light touch button operation, all functions can be set by buttons, which improves the safety and reliability of the product;

◆ All-digital calibration method, abandoning the old potentiometer adjustment, extremely convenient on-site use, and easy to control accuracy (this function is protected by a password);

◆ Press the button to directly set the transformation ratio of the test transformer (this function is protected by a password). When connecting testers of different voltage levels, the application is flexible and free, and it is true that one control box can be matched with multiple transformers;

◆ Status reminder function, full Chinese-guided operation, even if there is no manual, it can be manipulated skillfully;

◆ During the test, there are flashing high voltage symbols on the screen to remind the operator to pay attention to safety;

◆ Test result display function, which can automatically judge the test result (test passed or failed), and can reliably record the overcurrent, flash or breakdown voltage of the sample;

◆ Test result sound alarm function, when the test passes or fails, the equipment will emit different alarm sounds, and the test personnel can directly identify the test results by the alarm sound;

◆ Pause function, under automatic control, this function can realize the pause of boosting or depressing at any point, and the time of the pause can be flexibly controlled by the tester to facilitate the observation of the state of the test product;

◆ Automatic timing function. In automatic control, when the voltage automatically rises to the set value, the device automatically starts timing. When the timing expires, the test result is displayed and the device automatically returns to zero;

◆ Manual timing function. When manually controlled, the timer can be started manually. When the withstand voltage time is up, the device will automatically return to the zero position (only desktop devices have this function);

◆ Manual control mode, this mode is similar to the traditional electric boost/decrease method, the up/down is controlled by the button, the device automatically judges the upper/lower limit, there is overvoltage protection;

◆ The boost speed is intelligently controlled. When the voltage reaches 80% of the target voltage, the boost speed will automatically slow down. When it reaches 90% of the target voltage, the boost speed will further slow down;

◆Optional remote communication, door interlocking warning light alarm bell, external voltage divider verification interface, etc.;

◆ Using the combination of hardware and software anti-interference technology, stable performance and strong anti-interference.

Transformer drying method

induction heating method

This method is to put the body in the oil tank, and pass the power frequency current to the outer winding coil, and use the heat of the eddy current loss in the oil tank wall to dry. At this time, the temperature of the box wall should not exceed 115~120℃, and the temperature of the body should not exceed 90~95℃. For the convenience of winding the coil, try to make the number of turns of the coil as small as possible or the current is smaller. Generally, the current is 150A, and the wire can be 35~50mm2. Multiple asbestos strips can be placed on the wall of the fuel tank, and the wires are wound on the asbestos strips.

　　 hot air drying method

　　This method is to put the body in a drying room with hot air for drying. The inlet hot air temperature should gradually rise, and the temperature should not exceed 95℃. A filter should be installed at the hot air inlet to prevent sparks and dust from entering. Do not blow the hot air directly to the body, as far as possible from the bottom of the body to blow evenly in all directions, so that the moisture is released from the vent of the box cover.