FIELD: well drilling. SUBSTANCE: device has power supply and cable connected to the power supply and made in form of two-layer armour which is made of metal wires reeled upon pillow in form a spiral and wire of core; wires and core are short-circuited. Number of wires in external layer of the armour of end part with length no longer than 1.5 m is less than number of wires in external layer of the armour of the basic part. Total electric conductivity of armour of end part excesses over electric resistance of cable of the core no less than four times. EFFECT: improved efficiency. 3 dwg
