26/35kV 3x185mm2 Copper Tape Screen XLPE Insulated High Voltage Power Cable

Product Overview

At 26/35kV the electric field inside the insulation is high enough that a single void will destroy the cable within a few years of service. This three core 185mm2 cable is built on a vertical triple extrusion line with dry curing, where conductor screen, 10.5 mm XLPE wall and insulation screen are formed before the polymer has a chance to meet air. The result is a cable that passes partial discharge testing at 1.73 U0 for sixty minutes with readings below five picocoulombs.

A copper tape screen over the insulation screen carries the capacitive charging current, handles earth fault current, and provides the concentric neutral path expected by most utilities. The compacted copper conductor reduces the overall diameter, which matters when the cable has to pass through a 150 mm duct or a tight switchgear cable box.

Every drum is tested for partial discharge, dissipation factor and DC withstand before dispatch, and impulse test evidence to IEC 60502-2 is available for utility approvals. Our engineers also prepare the sheath bonding and earthing schedule, because at this voltage the bonding arrangement decides whether the sheath carries circulating current for the next thirty years.

Technical Specifications

Key Advantages

• Dry cured triple extrusion eliminates interface voids at 35kV field stress.
• Copper tape screen carries charging and fault current with a low impedance path.
• Compacted 185mm2 conductor keeps the diameter practical for 150 mm ducts.
• Every drum partial discharge tested below five picocoulombs before dispatch.
• Sheath bonding and earthing schedule prepared by our engineers with the cable.

Typical Applications

• 33kV and 35kV substation feeder circuits
• Ring main units and distribution switchgear connections
• Wind farm 33kV collector networks
• Mining, cement and steel plant high voltage reticulation
• Utility interconnection and transformer feeders

Quality Assurance and Test Data

Testing follows IEC 60502-2 including partial discharge, loss factor and impulse tests, with KEMA and CESI type test evidence available. We can arrange a third party inspector to witness routine tests at the factory if your utility requires it. At 26/35kV the copper tape screen and the 3x185mm2 copper conductor together define the fault duty, and both are verified on every drum we manufacture.

Ordering and Delivery Notes

High voltage orders move through type test review, drum approval and pulling plan before the first metre is extruded. We ask for the system voltage, fault level and bonding arrangement, then issue a drawing showing the copper tape screen connection points and the sheath voltage limiter positions. Drums are 250 m as standard because a 3x185mm2 assembly at this voltage becomes heavy quickly, and the pulling tension limit is printed on every drum flange.

Selection and Test Summary

• At 26/35kV high voltage the insulation wall drives cost, so the 3x185mm2 section is confirmed against the load before quoting.
• The copper tape screen is earthed according to the bonding schedule, which our engineers issue with the XLPE Insulated Power Cable.
• For a substation feeder the 26/35kV high voltage cable is delivered on 250 m drums with the partial discharge report attached.
• Where a non magnetic armour is required, the copper tape screen design can be combined with aluminium wire armour.

Frequently Asked Questions

Q: Why is partial discharge testing so important at 35kV?
A: Because voids inside solid insulation degrade under high field stress and lead to treeing failures. A low picocoulomb reading at routine test is the strongest practical proof that the insulation is sound.

Q: Should the copper tape screen be earthed at both ends?
A: Only for short runs or where induced voltage is acceptable; for longer feeders we provide a single point bonding or cross bonding design to avoid sheath circulating current.

Q: Can aluminium wire armour be supplied instead of steel tape?
A: Yes, aluminium wire armour is available for single core and three core variants where a non magnetic armour is required.

Q: What is the minimum bending radius on site?
A: Typically 20 times the cable diameter during pulling and 15 times after installation, and we provide a pulling tension limit with each drum.

Q: What pulling tension applies to a 250 m drum of this cable?
A: The limit is stated on the drum flange and depends on the copper tape screen and conductor mass; our engineers confirm it against your duct route before shipment.

Send your system voltage, fault level, route drawing and bonding preference, and our high voltage team will confirm the screen design, drum plan and delivered price for this 35kV cable.