When planning any electrical installation, choosing the right cable size is critical to ensure safety, performance, and compliance with electrical standards. One of the most commonly used cables in outdoor and industrial applications is 10mm SWA cable — and a key consideration is its current carrying capacity.
10mm swa current carrying capacity
In this article, we’ll explore everything you need to know about the 10mm SWA current carrying capacity, including factors that affect it, standard amp ratings, and how to choose the right cable for your project.
What Is SWA Cable?
SWA stands for Steel Wire Armoured. It's a type of armoured cable designed for underground or external use where mechanical protection is needed. A typical 10mm SWA cable consists of:
Conductors (usually copper)
XLPE insulation
PVC bedding and sheathing
Steel wire armour for protection
This type of cable is ideal for power distribution in residential, commercial, and industrial installations.
10mm SWA Cable Amp Rating
So, what is the current capacity of 10mm SWA cable?
Under standard installation conditions (buried direct in the ground or clipped direct), the ampacity (amp rating) of a 10mm² 2-core copper SWA cable is typically around:
57 to 65 amps for single-phase systems (depending on installation method and ambient temperature)
Up to 70 amps under ideal conditions (clipped direct, low ambient temp)
However, several factors influence the 10mm SWA current carrying capacity, including:
Installation method (buried, duct, conduit, tray, etc.)
Ambient temperature
Cable grouping (derating may apply)
Soil thermal resistivity (for underground installations)
Number of cores (2-core, 3-core, 4-core, etc.)
👉 For example:
Clipped direct: ~65A
Buried in duct: ~55A
Laid in free air: ~70A
⚠️ Always refer to the local wiring regulations or consult an electrician to ensure compliance.
Voltage Drop Consideration
Aside from the SWA cable amp rating, voltage drop must also be considered — especially over long distances. The larger the cable size and the shorter the distance, the lower the voltage drop.
You can use our free voltage drop calculator to check if your selected 10mm² armoured cable meets the voltage drop requirements for your installation.
Applications of 10mm Armoured Cable
Thanks to its durability and amp capacity, 10mm SWA cable is suitable for:
Garden offices and outbuildings
EV charger supply
Industrial power circuits
Outdoor lighting and equipment
Sub-main distribution
It offers a good balance between current capacity, mechanical strength, and ease of installation.
FAQs
❓ What is the maximum current for 10mm SWA cable?
Under ideal conditions, around 65–70 amps. But actual capacity depends on how it's installed.
❓ Can I use 10mm SWA cable for a 60 amp breaker?
Yes, in most cases, a 10mm² cable is suitable for a 60A breaker, but you must verify based on installation method and voltage drop.
❓ What size SWA cable for 10kW load?
A 10kW load at 230V single-phase draws about 43.5A. A 10mm² SWA cable would be sufficient, depending on the distance and installation conditions.
Conclusion
The 10mm SWA current carrying capacity generally falls between 55A and 70A, making it a popular choice for medium-power outdoor and underground circuits. Be sure to account for voltage drop, installation environment, and regulatory requirements before selecting your cable.
🔌 Need help choosing the right cable? Contact TOT Wire & Cable for expert advice and competitive pricing on all sizes of SWA armoured cables.
