When you are running power underground or through a construction site where mechanical damage is a real threat, standard cables just won’t cut it. You need protection. You need reliability. You need the industry’s best XLPE insulated SWA power cable.
If observed on a bill of materials as BS 5467 cable, YJV32 armored cable or just “SWA” the intent is the same: providing a safe solution for carrying mains supply in rugged environments. But the wrong spec or applying it wrong can result in costly failure.
This isn’t just a datasheet. This is your field manual. We’re going to strip back the layers of steel wire armored cable, show you why XLPE insulation is so much better than old-school PVC, and walk you through the installation gotchas that really confuse contractors.
What is XLPE SWA Armored Cable?
At its core, XLPE SWA Armored Power Cable is a low voltage (typically 0.6/1kV) mains supply cable designed for maximum durability. It is standard in the industry for use in mains distribution systems, industrial control systems, and cable ducting systems where protection against crushing or cutting is necessary.
Technically, the cable is a combination of XLPE (Cross-Linked Polyethylene) for high quality insulation and SWA (Steel Wire Armor) for mechanical protection.
The Standards Game: BS 5467 and IEC 60502
IEC 60502 is commonly used for international projects. Navigating part numbers is tricky. If you are sourcing for European machinery or projects following VDE standards, you will frequently see the code N2XRY. This designation refers to the exact same construction: Copper conductor (N), XLPE insulation (2X), Round Steel Wire Armor (R), and PVC outer sheath (Y). In the Chinese market, which provides a big chunk of infrastructure world-wide, this is very similar to YJV32 0.6/1kV XLPE SWA Armoured Power Cable.
- Y: Polyethylene insulation (in case the insulation is XLPE).
- J: Cross-linked ( in the case of modern cables it is sometimes implicitly included in the Y designation).
- V: PVC Sheath.
- 32: Steel Wire Armor with a pvc outer sheath.
When buying worldwide, knowing that YJV32 armored cable is the equivalent of BS 5467 allows you to find the best quality materials for your budget.
Anatomy of the Cable: Breaking Down the Layers
To understand why this underground power cable is so tough, you have to look at how it is built. Each layer serves a specific engineering purpose.
The Conductor: Class 2 Stranded Copper
Most SWA cables use Plain Annealed Stranded Copper (Class 2). We utilize stranded copper rather than solid conductors because flexibility is vital. Wrestling a solid-core armored cable into a trench is nearly impossible.
Insulation: XLPE (Thermosetting) vs. PVC
This is the single biggest upgrade in modern cable tech. Older cables used PVC insulation. Today, we use XLPE insulated armored cable.
- PVC (Thermoplastic): Softens when hot. Max operating temp is roughly 70°C.
- XLPE (Thermosetting): The molecules are chemically cross-linked. It doesn’t melt; it chars. It handles operating temperatures up to 90°C.
Why does this matter? A higher temperature rating means you can push more current (Amps) through the same size cable. It makes the XLPE SWA armored power cable specifications superior to older PVC counterparts.
Bedding
Between the armor and the inner cores lies the bedding. Usually made of PVC, it provides a cushion. Without it, the steel wires would grind into the soft XLPE insulation when you bend the cable, causing a short circuit.
Armor: Galvanized Steel Wire (SWA)
This is the shield. A single layer of galvanized steel wires is wrapped helically around the bedding. It provides:
- Tensile Strength: It stops the cable from snapping if pulled.
- Crush Protection: It resists spades, rocks, and heavy machinery.
- Earthing: The steel armor can be used as a Circuit Protective Conductor (CPC), provided the conductivity is calculated to be sufficient.
Sheath: The Outer Defense
The top layer is generally black PVC. It is ultraviolet resistant, so you can lay the cable in the sun outdoors without it cracking. For tunnels or public buildings, you could replace the normal PVC by Low Smoke Zero Halogen (LSZH) materials to comply with BS 6724.
Why Choose SWA? (SWA vs. STA vs. AWA)
One of the most common questions procurement managers ask is: “Why do we need SWA? Can’t we use tape armor?”
SWA vs. STA (Steel Tape Armor)
Steel Tape Armor (STA) consists of metal tape wrapped around the cable.
- STA is great for crush resistance (vermin protection).
- SWA offers crush resistance PLUS tensile strength.
If the cable will be pulled through a duct or suspended vertically, you must use steel wire armored cable. The wires grip and hold tension; tape will just unravel or snap.
The “AWA” Trap: Single Core Cables
Warning: Never use Steel Wire Armor on a Single Core mains cable. By passing AC current through a single core surrounded by magnetic steel, you create a magnetic field that heats up the armor (induction). This can melt the cable.
For single-core cables, you must use AWA (Aluminum Wire Armor). Aluminum is non-magnetic. If you are ordering XLPE SWA Armored Power Cable for a 3-phase system, SWA is fine because the magnetic fields cancel each other out.
Technical Specifications & Current Ratings
When designing an installation, the ”ability to carry current” (ampacity) must be known. Due to XLPE insulation, these cables are suitable for continuous operation at 90°C.
Here is a simple rule of thumb for BS 5467 copper cables (direct buried, ground temperature 15°C):
| Cross Section (mm²) | Approx Current Rating (Amps) – 3 Phase |
|---|---|
| 6mm² | ~53 Amps |
| 10mm² | ~73 Amps |
| 16mm² | ~96 Amps |
| 25mm² | ~123 Amps |
| 95mm² | ~294 Amps |
| 240mm² | ~517 Amps |
Note: Always calculate for voltage drop and de-rate for grouping factors using BS 7671 or IEC 60364 standards.
Voltage & Temperature
- Voltage Rating: 600/1000V (0.6/1kV).
- Operating Temp: -25°C to +90°C.
- Short Circuit Rating: High thermal stability allows XLPE to withstand momentary spikes up to 250°C.
Installation Best Practices: The Field Guide
Even the best XLPE SWA armored power cable manufacturer cannot save you from specific installation errors. Here is how to do it right.
Direct Burial vs. Ducting
Can you bury XLPE SWA armored cable for underground installation directly? Yes. That is what it is built for.
However, it should be laid on a bed of sand (to prevent sharp stones from piercing the sheath) and covered with cable warning tape. If laying under a road or concrete, always use a duct to allow for future replacement without digging up the pavement.
Gland Selection: BW vs. CW
You cannot just use any gland. The gland must terminate the armor wires securely to ensure earth continuity.
- BW Glands: For indoor use (dry). They clamp the armor but do not provide a waterproof seal.
- CW Glands: For outdoor use. They clamp the armor and have a compression seal ring to stop water entering the cable.
- E1W Glands: Double seal for highly hazardous or wet environments.
The “Banjo” Earth Tag
The armor is made of metal; it has to be grounded. When you thread the gland into a metal enclosure, you may get an earth contact, but it is not to be relied on.
Use an “earth tag” (banjo shaped) beneath the gland and enclosure at all times. Bolt a fly-lead from the tag to your main earth terminal. This guarantee that if a fault breaches the armouring, the protection device trips immediately.
Minimum Bending Radius
Don’t pull the cable too hard. Bending it too tightly crushes the bedding and forces the steel wires into the insulation.
- Dynamic (during installation): 8x Overall Diameter.
- Static (fixed): 6x Overall Diameter.
Conclusion
Choosing the right cable is about balancing mechanical protection with electrical performance. XLPE SWA armored power cable offers the perfect middle ground: it is tough enough to survive a construction site, flexible enough to install, and powerful enough to run main distribution networks.
Whether your spec sheet lists BS 5467, YJV32, or N2XRY, ensuring you select the correct size of XLPE insulated SWA power cable and glanding it properly will guarantee a power supply that lasts for decades.
Ready to source high-grade SWA cable? Contact our engineering team today to discuss your project requirements or verify your cable sizing calculations.
