Why do we use rod gaps across the bushing of a pole-mounted transformer?

Rod gaps are also known as arcing horns and are installed on PMTs (pole mounted transformers) to protect them against overvoltages due to lightning strikes and faults etc.
It has a non linear resistive property which acts as high resistance during normal operating voltage and exhibits low resistance property during high voltages and causes the arc due to lighting to ground in order to prevent the asset from damage.

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Rod gaps are also known as arcing horns and are installed on PMTs (pole mounted transformers) to protect them against overvoltages due to lightning strikes and faults etc.

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