The aging test is the minimum input voltage of the power supply, the maximum load working state, the maximum working current at the primary side of the transformer, and the maximum temperature rise.

There are many factors that may cause coil short circuit during aging test, we propose the following reasons based on production experience.

1) Magnetic core material problem:

With the rise of temperature, the magnetic core inductance decreases, the power consumption increases, the primary side working current gradually increases, and finally leads to magnetic saturation, the primary side current sudden change, the over-current leads to the high current density of the conductor, and the thermal melting loss of the insulation skin leads to the turn-to-turn short circuit burning;

2)Quality problem of copper wire:

The inter-turn insulation strength caused by pinhole or damage is weak, and the insulation strength gradually weakens with the temperature rise during the test, which eventually leads to short circuit burning;

3)The problem of interlayer insulation tape:

The damage leads to a large inter-turn (inter-layer) potential difference, and the inter-turn leakage current will deteriorate with the temperature rise, and the insulation strength will gradually increase, resulting in a bad short circuit;

4)Production process problem:

The insulation strength is weak and the leakage current is high due to various factors (for example, the wire clamping head, the interlayer tape wrapping deviation, the winding layer falling, the insulation tape wrapping deviation and isolation failure, etc.).

We need to pay attention to the causes of the above faults when testing switching power supply transformers.

If there are any technical issues with the product, we will actively provide after-sales solutions to customers.