Why can't R-type power transformer be overloaded?

In daily life, we may encounter overload when using R-type power transformers. What is the cause of transformer overload? Can the transformer work normally after overload? With these questions, let us understand the emergency treatment of power transformer overload and some precautions for transformer operation.

R type power transformer

What is the impact of transformer overload on the transformer itself:

1. Transformer loss increases. Transformers are generally designed according to rated capacity, and the operating balance point is around 67%. When the transformer load exceeds the rated capacity, the transformer copper loss will continue to increase, increasing the transformer loss.

2. When the output voltage of the transformer exceeds the rated capacity of the transformer, the secondary output voltage of the transformer decreases, and when the output current reaches the short-circuit current, the voltage drops to 0.

3. The service life of the transformer will be reduced. The windings of the transformer are mainly made of insulating materials, which require sufficiently high heat resistance. If the temperature is too high, the insulating material will age rapidly. Moreover, if the transformer is overloaded for a long time, the transformer temperature will be too high, and in severe cases, the transformer will burn.

Can a transformer be overloaded? The answer is yes. Under normal circumstances, the transformer can be operated within the load value it can bear for a short period of time, but this time period should not be too long. If it is operated at emergency load for a long time, the service life of the transformer will be shortened to varying degrees, and this operation mode should be minimized. When overload operation is necessary in an emergency, the over-rated current operation time should be minimized and the over-rated current multiple should be reduced. The normal rated value transformer should be replaced in time.

So under what circumstances is it normal for the transformer to be overloaded? When the average aging rate is small, the transformer can be operated at overrated current for a short period of time. In the following circumstances, it cannot be overloaded.

When the transformer has serious defects or insulation weaknesses, the transformer should not exceed the rated current. The normal rated transformer should be replaced immediately, because when such problems occur, the transformer has already failed. At this time, if it is overloaded, it will increase the safety risk caused by the transformer failure.