I have a thermal arc lt-300 tig welder i have used sucessfully for years at my old shop on 460 three phase power. I recently moved to my new shop where it is 208v three phase and I cannot get it to work, the warning light illuminates which means I have an incoming voltage issue. I opened it up and could not find a jumper to change input voltage and I rewired the three leads in different orders to make sure phase was correct to no avail. Any suggestions? Thanks