Help needed please! I am trying to work out the correct size of SWA Armoured Cable to use. The source is mains voltage from an agricultural distibution point. The destination is 450m away. The current is 35 amps. The voltage drop has to be as close to legal as possible! (I think thats 5%) The cable will be underground in scotland so ambient temp of 0c to 20c. I need to know the diameter of the cable to use! Please please help....many thanks!!