The Characteristics of High Voltage Power Cable

Application:

High voltage cable refers to the amount of voltage power that is above the regular norm or threshold. There are two points related to high voltage that describes its essence: it causes sparks in the air and the fact that it can give out electric shocks when one goes close to it. The voltage could be concerning two conductors of a system or a conductor and the ground. For instance, when it comes to electric power transmission, any voltage above 35,000 volts is considered high voltage. The apparatus’ design and insulation are essential to include for its classification.

Standard:

Insulation Screen:

The insulation screen consists of an extruded layer of non metallic, semi- conducting compound extruded over the insulation. The extruded semi-conducting layer shall consist of bonded or cold strippable semi-conducting compound capable of removal for jointing or terminating. As an option, a semi-conducting tape may be applied over the extruded semi-conducting layer as a bedding for the metallic layer. The minimum thickness is 0.3 mm and the maximum resistivity is 500 Ohm-m at 90°C. The screen is tightly fitted to the insulation to exclude all air voids and can be easily hand stripped on site. The insulation screen is not necessary for both PVC and EPR/HEPR insulated 1.8/3KV and 3.6/6KV cables. The screen may be covered by semi-conductive water blocking swellable tape to ensure longitudinal watertightness.

Metallic Layer:

The metallic layer may be applied over the individual cores or the core assembly collectively. The following types of metallic layers are provided: 1) Metallic Screen 2) Concentric Conductor 3) Metallic Sheath 4) Metallic armour The metallic screen shall consist of either copper tapes or a concentric layer of copper wires or a combination of tapes and wires to provide an earth fault current path. The concentric conductor is applied directly either over the insulation, or over the insulation screen or over an inner covering. The metallic sheath consists of lead or lead alloy applied as a tightly fitting seamless tube. The metallic armour consists of either flat wire armour, round wire armour, and double tape armour.

Lapped Bedding (for armoured lead sheathed cable):

The lapped bedding consists of either impregnated/synthetic compounded paper tapes or a combination of two layers of these paper tapes followed by a few layers of compounded fabulous materials. The thickness is around 1.5mm

-Armour (for armoured cable):

The armour consists of round aluminium wire armour applied helically over an extruded separation sheath.

Over Sheath:

Overall sheath comprises a layer of extruded thermoplastic compound (PVC, PE or LSZH can be offered as an option.) or elastomeric compound (polychlorprene CSP or chlorosulfonated PE). The nominal oversheath thickness is calculated by 0.035D+1 where D is the fictitiuous diameter immediately under the oversheath in mm. For unarmoured cables and cables with the oversheath not applied over the armour, metallic screen or concentric conductor, the nominal oversheath thickness shall not be less than 1.4mm. And for cables with oversheath applied over the armour, metallic screen or concentric conductor, the nominal oversheath thickness shall not be less than 1.8mm.

HIGH VOLTAGE POWER CABLES:

We provide high-voltage power cables with a maximum cross-sectional area of 2,500mm2 and rated system voltages of up to 240kV. The cables are manufactured from high-quality materials in state-of-the-art facilities and they conform to both national and international quality and safety standards.