why there is fault in transformer while raining
Answers
Usually, this happens when an underground transformer attached to your home gets wet and short circuits. Sometimes this happens when you do not secure the transformer with something that will keep water from going into its capacitors or contactors or wires themselves. You might see electrical sparks, arcs, or explosions from these transformers if they short circuit and usually with these happening, power outages are usually likely.
But for other reasons, the power goes out usually in 2 ways -
During a rainstorm, winds of 45 to 50 mph or more sustained can cause brownouts and short-term outages. 50 mph winds or higher can cause tree limbs or branches on top of power lines to snap and fall down on power lines which can in turn snap or break leading to power line transformer explosions and resultant outages.
During a rainstorm where there is lightning (as seen in thunderstorms or thundershowers), a cloud-to-ground lightning hit (or strike) on a power line or the transformer can break or shatter the power line and/or blow up the transformer, causing much more quicker and much longer power outages.