Small in size, light in weight, speedy in smelting , simple in operation, easy in erection and movement; ready for operation when power supply, induction coil and inlet and outlet pipelines get connected; less power consumption with less than 0.3 Kw/h for average per smelting of 1 kg gold; with over-current,over-voltage, under-voltage, water deficiency, over-temperature and other protection functions; applied for roughing of gold and smelting of white silver and other uses