... the following parts: Medium frequency smelting furnace(10kg, 25kg, 50kg, 100kg, 200kg), holding furnace, (10kg, ... medium frequency power source, holding furnace power source system(10kg, 25kg level ones are not equipped with holding furnace) and so on. 3.1 Induction ... furnace’s power source. The resistance heating one is heavy current power regulator and the induction heating one SCR medium frequency ...