I am making a eBIAB system with 1 PID and 1 4500W element. At 240V this should pull 18.75A. I will be moving soon and plan to use the dryer plug and Spa panel so i think there is a chance it could be 220V which means 20.5A. However I think I read somewhere that the resistance of the elements is static so a 4500W element on 220V will run slightly under 4000W (18.2A). Is this correct? I want to use 20A plugs to save on cost and 4500W should be more than enough power for my 5 gal batches.