AVO Substation Maintenance II Practice Test

When the oil can no longer hold any more dissolved gases, the gases are released into the headspace above the oil. This occurs because the solubility of gas in oil is limited—once the saturation point is reached, any additional gas will no longer remain dissolved. Instead, it will form bubbles or migrate to the area above the oil known as the headspace.

Understanding this concept is crucial in managing oil-filled equipment, such as transformers, as the presence of excessive gas in the headspace can indicate issues like overheating or partial discharge, which can lead to equipment failure. Monitoring and assessing gas levels in the headspace is an important aspect of maintenance and diagnostic practices in substations.