| 摘要 |
A heating cable is substantially free from electromagnetic field, and comprises a pair or spirally twisted heating wire elements, a tubular sheath made of electrically conductive material covering the pair of spirally twist ed heating wire elements, and possibly an insulating jacket covering the tubula r sheath. When the spirally twisted heating wire elements are supplied with a current of given amplitude flowing in opposite directions in the heating wir e elements, the electromagnetic fields from the respective wire elements cance l each other to provide a heating cable substantially free from electromagneti c field. A method of fabricating the heating cable is also disclosed.
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