After the ac capacitor bank has been working for a period of time, it is always found that the outer shells of individual capacitors begin to deform. This is what we often call the "bulging/bulging" phenomenon.

Capacitor bulging is one of the most common capacitor failures, which can easily cause more serious consequences such as fire and explosion, and then negatively affect the safe and stable operation of the capacitor.

The solution to replace the capacitor bulge is simple and clear, but only by understanding why the ac capacitor bulges and how to prevent it can be truly "saving"!

Why does the ac capacitor bulge?

1. The operating temperature is too high and the temperature has not been properly cooled. After the capacitor starts to run, its own temperature will rise. If it exceeds the reasonable range specified by the manufacturer, the insulation aging will be accelerated. If no cooling measures are taken, the internal insulating oil will generate gas, which will then cause the capacitor to deform and bulge.

2. Overvoltage operation of the capacitor. If the capacitor is operated with overvoltage for a long time, the internal metalized film will accelerate the aging due to the high temperature, and then increase the internal pressure of the capacitor, which will cause the capacitor to bulge when it exceeds the range of the shell.

3. Capacitor overcurrent operation. Over-voltage and over-current of the capacitor will cause its overload operation, which will not only cause serious heating of internal components, but also membrane breakdown, which will generate gas inside the capacitor, increase internal pressure, and then cause bulging.

Once the capacitor bulges, it proves that there has been a problem. If left alone, the internal insulating oil of traditional oil-type capacitors will leak out and oil leakage will occur; if the capacitor is severely bulging, its temperature will be as high as the ignition point of the internal components, which will cause the capacitor to ignite, and the internal and external pressure difference will exceed the critical point. Will cause an explosion.

How to prevent ac capacitor bulging?

1. Select the appropriate voltage level, and perform daily operations as required to avoid frequent switching and live switching, and reduce the impact of large currents.

2. Detect the ambient temperature of the capacitor bank, and take timely cooling and ventilation measures when the temperature is too high.

3. Strengthen daily inspection and maintenance, find the special condition of the capacitor in time, and solve and prevent it early.

If the capacitor bulge is not serious, can it still be used?

Most people know that they need to be replaced immediately when they find that the ac capacitor has a serious bulge. Now the question is whether the capacitor can continue to be used if the capacitor is not severely bulged.

If it is really a slight bulge (to a negligible degree), it can be used for a short period of time, but it should also be prepared for replacement.

Under normal circumstances, if the capacitor bulges, you should immediately exit the operation, because the bulge will only get more and more serious. If there are serious consequences, the gain will not be worth the loss!