Ring transformer is a kind of electronic transformer, commonly known as "ring cow". In addition to electronic equipment with high technical requirements, it is also widely used in household appliances such as power amplifiers. The damage of ring transformer has its inherent law, so we only need to find the cause of the damage and prescribe the right medicine to repair the ring transformer.

Causes of ring transformer damage

One is the ring bull heating damage caused by load short circuit; There is also a kind of damage caused by turn-to-turn short circuit caused by high voltage of power grid or insulation damage of winding itself.

Among the common faults, only one 220V high-voltage winding is damaged in the ring pressure section, and the other low-voltage windings are intact. However, the 220V winding mostly adopts double-wire parallel winding mode, which is not the single-wire winding mode adopted by ordinary square transformers.

The turn-to-turn voltage of double-wire parallel winding method is much higher than that of single-wire winding method, so the probability of turn-to-turn short circuit of enameled wire under high voltage is much higher than that under low voltage under the same conditions, so the double-wire parallel winding method is more likely to cause turn-to-turn short circuit than the single-wire winding method. It can be seen that the maintenance of ring transformer can be changed from double-wire parallel winding to single-wire winding.

Maintenance method of ring transformer

1. First remove the damaged outer packaging, insulating tape and low-voltage winding one by one, observe the winding mode of each winding and make records, and keep the enameled wire and insulating tape of each winding for later use. Because the innermost layer is a 220V high-voltage winding with many turns, if it has been blackened and deformed, it must be removed to find the enameled wire of the same specification for standby;

2. Clean the silicon steel sheet and evenly wrap it with insulating tape as the innermost layer. Enamelled wires are connected with thick and soft threads as outgoing wires, and then evenly arranged and wound. It is required that the inner coils are arranged tightly and smoothly, and there can be no overlap. After winding one layer (the head and tail of the enameled wire should not be too close, and the interval should be reserved with insulating tape), you can brush some insulating paint of the motor on it to increase the reliability, and then use insulating tape to wind another layer on it, and continue to wind the second and third layers;

3. After winding the second floor, the no-load current of the ring bull can be measured by multimeter alternating current, and the no-load current is required to be below 50mA. If it is too large, it means that the number of turns is not enough. Continue winding until the current drops below 50mA. Connect the lead-out terminals and paint them with insulating paint. Do a good job of interlayer insulation of high and low voltage windings, and then wind each low voltage winding according to the recorded winding method (the low voltage winding may not be coated with insulating paint, but interlayer insulation is required). Finally, wrap the outermost insulating tape. After shaping, the power supply can be turned on to test whether the voltage of each winding meets the requirements. After passing the test, you can start the machine.

The above is the specific method of ring transformer maintenance, hoping to help everyone.