COAXIAL THREE-PHASE HEATING CABLE Russian patent published in 2014 - IPC H05B3/56 

FIELD: electricity.

SUBSTANCE: invention is related to electrical heating cables and namely to designs of coaxial three-phase heating cables intended for heating of objects with different shape, size and purpose. The cable has three cores 1, 2 and 3, each core is covered with an external heat and electric insulating sheath 4, it has an inner 5 and outer 6 conductors interconnected in series and placed coaxially with an annular gap between them filled with the inner heat and electric insulating sheath 8, and a common protective jacket 9. Cable strands are identical and twisted. The jacket 9 has three layers, the lower layer 10 and the upper layer 11 are made of the heat and electric insulating material while the middle layer is made in the form of a metal wire braid 12, which can be earthed PE at the point of the cable connection to the electric mains and the point of in-series connection 7 of the inner 5 and outer 6 conductors. The outer conductors 6 of each core are interconnected at the final point and form an artificial earthing point.

EFFECT: improving electrical and fire safety of the cable, flexibility in any direction, linear heat power, reliability, service life, reducing power consumption and expanding the scope of application.

2 cl, 1 dwg