Types of Electrical Cables and When to Use Them

A practical guide to electrical cable construction, the difference between conductor and insulation choices, and the main cable types used in UAE building and infrastructure projects, with sizing and code notes.

Armoured cable cross-sectionOuter sheath (PVC)Steel wire armourBeddingInsulation (XLPE/PVC)Conductor (Cu/Al)

An electrical cable is more than a wire: it is an engineered assembly of one or more current-carrying conductors, insulation, and often a protective sheath or armour. Choosing the right cable determines whether a circuit is safe, efficient and durable for its full design life.

The wrong cable choice causes overheating, voltage drop, premature insulation failure, or fire risk. In the UAE's hot climate and demanding building codes, correct cable selection and sizing is a core part of every compliant electrical installation, from a villa distribution board to a substation feeder.

How it works

Conductor material. Most cables use copper (Cu) or aluminium (Al). Copper has higher conductivity and is easier to terminate, so it dominates smaller circuits and final wiring. Aluminium is lighter and cheaper for a given current, so it is common in larger feeders and distribution cables, but needs a larger cross-section and careful terminations.

Insulation. The insulation separates conductors and withstands voltage and heat. The two most common materials are PVC (polyvinyl chloride), rated to about 70 °C conductor temperature, and XLPE (cross-linked polyethylene), rated to about 90 °C, which allows a higher current rating and better thermal performance for the same size.

Voltage grade. Cables are classified by their rated voltage: Low Voltage (LV) up to 1 kV (e.g. 600/1000 V building cables), and Medium Voltage (MV) typically 3.3 kV up to 33 kV for distribution and substation feeders. Each grade has matched insulation thickness, screening and testing requirements.

Sizing and derating. A cable's cross-section (mm²) is selected so it can carry the design current without overheating, while keeping voltage drop within limits (commonly around 3–5% in building codes). The base current rating must be derated for high ambient temperature, grouping of cables, and the installation method — all critical in the UAE, where ambient and ground temperatures are high. Sizing follows standards such as IEC 60364 and the manufacturer's tables, and must coordinate with the protective device (fuse or breaker).

Main types

Single-core cableOne conductor per cable; used in larger feeders and where individual phase routing or flexibility is needed.
Multi-core cableSeveral insulated conductors in one sheath; common for final circuits, distribution and three-phase supplies.
PVC-insulated cableEconomical general-purpose cable rated to ~70 °C; common for indoor wiring and lower-temperature duties.
XLPE-insulated cableHigher temperature rating (~90 °C) and higher current capacity; widely used for LV and MV power cables.
Armoured cable (SWA / AWA)Steel or aluminium wire armour provides mechanical protection; used for buried, external and industrial runs.
Flexible cableFinely stranded conductors for movement and connection to portable or vibrating equipment.
Fire-rated / fire-resistant cableMaintains circuit integrity during a fire; used for life-safety systems such as fire alarm, smoke control and emergency lighting.
Control / instrumentation cableSmall multi-core (often screened) cables carrying signals for controls, BMS and instrumentation.

In the UAE

How GPR applies this

GPR specifies, sizes and installs LV and MV cabling for residential, commercial and industrial projects across Abu Dhabi, selecting conductor material, insulation and armour to suit each circuit, load and environment. Our teams apply correct derating for the local climate and coordinate cable selection with protective devices and earthing to meet ADDC/DoE wiring regulations. For life-safety circuits we install certified fire-rated cabling in line with UAE Civil Defence requirements.

Frequently asked questions

What is the difference between copper and aluminium cables?

Copper conducts better and terminates more easily, ideal for smaller and final circuits; aluminium is lighter and cheaper for large feeders but needs a bigger cross-section and careful terminations.

What does XLPE mean and why is it better than PVC?

XLPE is cross-linked polyethylene insulation rated to about 90 °C, versus about 70 °C for PVC, so an XLPE cable can carry more current and handle higher temperatures for the same size.

When do I need an armoured (SWA) cable?

Where the cable needs mechanical protection — buried in the ground, run externally, or in industrial areas at risk of impact or rodent damage.

What is a fire-rated cable used for?

For life-safety circuits that must keep working during a fire, such as fire alarm, smoke-extract, and emergency lighting systems, as required by the UAE Fire and Life Safety Code.

How is the correct cable size chosen?

By matching the conductor cross-section to the design current with derating for ambient temperature, grouping and installation method, keeping voltage drop within limits, and coordinating with the protective device per IEC 60364.

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GPR designs, installs and maintains MEP systems across Abu Dhabi and the UAE.