Woocommerce Min max price issue [Help Please]

I am running a wordpress eCommerce website developed with woocommerce wp plugin and theme.. What i want is when user purchase of Rs 500 they should not be charged for delivery or if user make purchase above 500 then delivery should be free
Whole functionality should be done automatically.. there might be plugin for this.. Help me if anyone can.. i need this function in my website now..

See original post by Rinki12