Why A.C needs more insulation than D.C at same voltage level?

potential stress on the insulation is less in DC than in AC system

For the same working voltage, the potential stress on the insulation is less than in case of DC system than that AC system. Therefore , a DC line requires less insulation.   In other words A DC System has a less potential stress over AC system for same Voltage level and power rating, this is why AC needs more insulation than DC system.

A.C needs more insulation than D.C because of potential stress on the insulation that is less in D.C than A.C system

because of the potential stress on the insulation is less than in case of DC system than that AC system. Therefore , a DC line requires less insulation.

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