Nominal voltage: 10 kV. Testing voltage 18 kV
Type : IPO 13 i IPO 13-A, NPO 13 i NPO 13-A
JUS N.C5.020

Construction:
Conductor: Wire of stranded copper or aluminium conductor.
Core: Paper tape insulated conductor
Cable core: Cores laid up and wound with paper tape layer and all impregnated with normal or semi - hard compound
Sheath: Seamless lead or lead alloy tube
Inner protection: Impregnated paper or jute with bitumen compound covers.
Mechanical protection: Two steel tapes
Outer protection: Impregnated jute with bitumen compound covers
Application: In urban and industrial networks for direct burial into ground. NPO 13 type is applied for inclined or vertical installations.

CONSTRUCTION ELEMENTS

CONDUCTOR
Cable conductor are made either of copper or aluminium as multi - wire sector shaped.
The construction of copper and aluminium conductors and electrical correspond to JUS N. C0. 015 Class2.

INSULATION
Insulation consists of several impregnated paper tapes helically wrapped up around conductor.
The winding is carried out on machines what enables a precise and firm setting of paper tapes, therefore the creation of vertical gaps and air spacings which are liable to ionisation are not possible.
In attached Tables the insulation thickness between conductors is designated by Symbol P/P and between conductor and sheath by P/O

CABLE CORE
Cores of multi-core cables must be mutually laid up, while the space between cores filled up with paper or jute yarn to obtain better thermal characteristics and circular core shape.
The paper tape insulation helically wrapped up around cable core is placed over stranded cable cores up to 10 kV. Besides mechanical strengths this belt insulation increases dielectric strength between conductor and metal sheath.

CABLE IMPREGNATION
Paper insulation is dried up and impregnated in a special impregnation unit.
Impregnation is carried out with normal compound.

CABLE SHEATH
Metal sheath is made by extruding of metal in hot condition in the form of a seamles tube.
Metal is either lead or aluminium.
Metal sheath are made on hydraulic or continuous presses.

ANTI - CORROSION AND MECHANICAL PROTECTION CABLES