co 回複：三相變單相容易，單相變三相難，不是不可以，能實用的超貴，

just pass the 3 phase heater. To convert from 1 phase to 3 phase, a converter need to convert 1 phase AC to DC and then DC to 3 phase AC. These electronics (power) will be easy to broken (lots of heat generated during the conversation).