Paying off: On a normally operating enamelled machine, most of the operator's energy and physical strength are consumed in the paying off part. Replacing the paying off reel makes the operator pay a lot of labor. The quality problems and operation failures are easy to occur on the line to line joints. The effective method is to pay off in large capacity. The key of paying off is to control the tension. When the tension is large, it will not only thin the conductor, make the surface of the conductor lose brightness, but also affect many properties of the enamelled wire.