In electrical installations, CPC typically stands for Circuit Protective Conductor. This is the earth wire used to protect both people and electrical systems by providing a low-resistance path to ground in the event of a fault.
cpc cable
In some contexts, CPC may also refer to Custom Power Cord or Commercial Power Cord, especially in IT and industrial environments.
CPC Cable Meaning in Electrical Wiring
When referring to CPC cable in the UK or EU:
It’s not a special cable type, but rather the earth conductor within a cable.
For example, in Twin & Earth (T&E) cable, the bare copper wire is the CPC.
In armoured cable (SWA), the metallic armour itself may act as the CPC.
Examples:
Twin & Earth 2.5mm²: Contains live, neutral, and bare CPC wire
SWA Cable: Uses the steel armour as the CPC, bonded at gland points
What Is a CPC Cord?
In the context of equipment power cords (North America):
'CPC cord' may refer to a custom-built power cord for commercial or industrial use
It can include specific connectors (IEC C13, C19, NEMA types), shielding, jacket types (PVC, LSZH), or voltage ratings
Used in servers, UPS systems, medical devices, and rack setups
Why Is CPC Important?
✅ Safety: Prevents electric shocks in case of insulation failure
✅ Compliance: Required by regulations such as BS 7671 (UK Wiring Regs)
✅ System Protection: Helps breakers or RCDs trip promptly during faults
CPC Cable Selection Tips
| Application | Cable Type | CPC Method |
|---|---|---|
| Domestic wiring | Twin & Earth | Bare earth wire included |
| Outdoor installation | SWA (steel wire armoured) | Use armour as CPC |
| IT racks/power cords | Custom power cords (CPC) | Ground pin in connector |
| Control cables | YY / CY / SY cables | Internal green/yellow wire |
CPC Cable vs Earth Cable
| Term | Description |
|---|---|
| CPC | General term for earth conductor in a circuit |
| Earth wire | Often refers to same thing in casual terms |
| Ground wire | US equivalent of CPC |
FAQs
Q: Is CPC the same as earth wire?
Yes, CPC refers to the conductor that performs the grounding function in a circuit.
Q: Can the armouring in SWA cable be used as the CPC?
Yes, when properly bonded and earthed, the steel armour can act as the CPC.
Q: What color is the CPC wire?
Typically green/yellow, though in some cables (like T&E), it may be bare copper and must be sleeved.
📌 Summary
Whether you're working with household wiring or industrial power cords, understanding the role of the CPC (Circuit Protective Conductor) is essential for safe and compliant installations. It may appear as a bare earth wire, an armour layer, or a ground pin in a cord, but its function remains vital.
If you're looking for CPC-compliant cables, armoured cables, or custom power cords, feel free to contact our team at TOT Wire & Cable for tailored solutions.
