Last updated: June 2026
Copper-Clad Aluminium (CCA) Ethernet cable is the most common hidden cause of PoE camera performance problems in UK installations. CCA cable looks identical to solid copper cable and is often sold at significantly lower prices, but its electrical resistance is 60% higher, it generates more heat under load, and it is physically brittle, leading to connector failures. The cost saving is never worth the reliability loss.
The Electrical Differences Between CCA and Solid Copper
Solid copper Cat5e has a DC resistance of approximately 0.188 ohms per metre per conductor at 20 degrees Celsius. CCA of the same gauge has a resistance of approximately 0.300 ohms per metre because aluminium has 61% higher resistivity than copper and the copper cladding layer is only 10–40% of the cross-section. Over a 50-metre run, solid copper produces 9.4 ohms round-trip resistance, while CCA produces 15 ohms. For a camera drawing 0.3 amps, the voltage drop at the camera end is 2.8 V for copper compared to 4.5 V for CCA.
Heat Generation and Fire Risk
The higher resistance of CCA causes more power to be dissipated as heat in the cable. A 15-watt load on a 50-metre CCA cable generates approximately 2 watts of heat in the cable itself, compared to 0.8 watts for solid copper. In a bundle of 4 CCA cables, the combined heat raises the ambient temperature around the cables by 10–15 degrees Celsius above the surrounding air. This heat accelerates oxidation of the aluminium core, further increasing resistance in a feedback loop. In extreme cases, cable bundles in enclosed spaces have been known to reach temperatures that degrade the PVC jacket.
Mechanical Fragility and Connector Failure
Aluminium is significantly more brittle than copper after repeated flexing. CCA cable terminated with RJ45 connectors experiences conductor breakage at the IDC (Insulation Displacement Contact) point after half the flex cycles that solid copper withstands. The aluminium core also creeps under constant pressure from the connector contact, gradually reducing contact force and increasing resistance at the termination point. After 12–18 months, a CCA termination can develop resistance high enough to cause intermittent link drops or PoE power failure. The failure mode is invisible because the connector appears intact externally.
How to Identify CCA Cable After Installation
CCA cable can be identified by scraping the conductor surface with a blade: copper-coloured surface reveals a white aluminium interior. The cable is noticeably lighter than the same length of solid copper cable. The cable jacket may be marked “CCA” or “CCAM” on the print line, but some manufacturers omit this marking. A magnet test is not reliable because aluminium is non-magnetic. The definitive test is resistance measurement with a multimeter: a 10-metre loop of the cable should read under 4 ohms for solid copper and over 6 ohms for CCA.
Video: How I Installed My PoE Camera: Cable Run, Drilling, Terminations, Mounting
Frequently Asked Questions
1. What is CCA Ethernet cable?
Answer: Copper-Clad Aluminium cable uses an aluminium core with a thin copper coating. It looks like solid copper but has higher resistance, lower strength, and is unsuitable for PoE CCTV installations. For more detail, see Best CCTV cameras for False Alarm Reduction in 2026 - UK buyer guide. Also read our related guide: IR Distance Spec Inflation: Manufacturer Lies. Browse our comprehensive CCTV knowledge base at CCTV Systems Guide. Official UK guidance on this topic: GOV.UK.
2. How can I tell if my Ethernet cable is CCA?
Answer: Scrape the conductor with a blade. If the exposed metal is white/silver, it is CCA. Weigh the cable: CCA is significantly lighter than solid copper. Check the cable jacket print line for CCA markings. For more detail, see How to install CCTV for Farms and Agricultural Property - UK step by step guide 2026. Also read our related guide: IP Rating Deception: IP67 Is Not Enough for UK Weather.
3. Can CCA cable damage my PoE cameras?
Answer: CCA can cause voltage drop that makes cameras reboot or underperform. The excess heat generated in the cable can also degrade the cable jacket and adjacent cables over time. For more detail, see How much does Schools and Education Settings CCTV cost in 2026? UK prices explained. Also read our related guide: Camera Warranty Traps: What Voids Your Coverage.
4. Is CCA cable legal for UK CCTV installations?
Answer: CCA cable does not meet the BS EN 50173 standard for structured cabling. Using CCA for PoE installations voids the installation warranty with most UK system integrators and may not comply with building regulations. For more detail, see Future of False Alarm Reduction CCTV in 2026 - UK trends and technology. Also read our related guide: WiFi Interference from Neighbours Plagues CCTV.
5. How much more does solid copper cable cost than CCA?
Answer: Solid copper cable costs approximately 30–60% more than CCA. For a typical 8-camera installation using 50 metres per camera, the total cable cost difference is £30–£60, which is negligible compared to replacement labour. Also read our related guide: 5 GHz vs 2.4 GHz for WiFi Security Cameras.
Conclusion
The difference between a security system that works and one that frustrates is understanding the real-world behaviour of cameras, cables, and the environment they operate in. Manufacturers sell specifications. Installers solve problems. The questions above represent the issues that UK homeowners and businesses actually face — the ones the spec sheets do not mention.
Article by Gary Pearce, qualified security systems engineer. For a free security assessment, visit gary-pearce-home-services.pages.dev. This guide was last updated June 2026. Verify current UK regulations with the ICO.