What is the difference between CCA, CCS, CCC and Pure Copper?

What is the difference between CCA, CCS, CCC and Pure Copper?

Copper can account for up to 80% of the cost of a cable, so it's no surprise that alternatives to copper are constantly being sought. The practice of replacing solid copper with copper aluminum (CCA) or copper clad steel (CCS) to save money is still common, so do you know what the differences are for you?

What is CCA?

The most common alternative to copper used in the electrical industry is aluminum. Widely used in power distribution, many aluminum cables buried under the road as power cables. CCA is an aluminum conductor with a thin copper coating. It is made by enclosing an aluminum rod in a layer of copper tape that is welded along the seam to completely enclose the aluminum. The entire rod is drawn through a series of rollers to reduce the diameter to just 0.1 mm, just over the thickness of a human hair. The main disadvantages are lack of flexibility, higher resistance and lower conductivity compared to copper. This means you have to use more of them to carry the same current or amps. On a power cord, this is usually not a problem as you only need to go up a size or two. It results in a larger overall cable using more insulation, shielding, but the savings made over an equivalent copper cable are significant. Aluminum is also used in some high frequency coaxial cables where aluminum can perform better than copper at very high frequencies (GHz). In both of these cases the aluminum is bare (silver in color) and easy to spot. It is not disguised to look like copper.

CCA has some advantages over solid copper, mainly around weight and cost. CCA is significantly lighter than copper and in some applications can offer advantages in cable containment and handling. Aluminum is about one-third the price of copper and therefore provides cost savings over solid copper conductors. Theft is also less likely with deeply discounted prices. It also has better corrosion resistance than plain aluminum

What is CCS?

CCS (copper clad steel) is similar to CCA in that a steel conductor is coated with a thin layer of copper. Steel gives greater mechanical strength than aluminum, but is heavier and less flexible. Of course it is also less conductive than copper. It is manufactured in the same way as CCA, where the applied copper is drawn to smaller diameters by means of rollers.

Higher mechanical strength creates a strong alternative to copper that minimizes physical damage during installation compared to aluminum. Problems arise when both CCA and CCS are referred to as pure copper cables. Nor are they suitable for applications where pure copper is specified and can cause long-term problems that can be expensive to correct once the cable is installed.

What is CCC?

Another major problem is the use of recycled copper as conductor material. Known as CCC (Copper Clad Copper), these conductors use low grade copper alloys made by mixing recycled copper with impurities such as brass, tin and other contaminants and forming it into 8mm bar. This is then coated on copper foil and reduced using the same process as CCA resulting in an impurity-filled conductor with a very high oxygen content and resistance that can be even higher than aluminum. This can be very difficult to detect as the conductor appears "yellow" (like copper when cut). The best way to check is to measure the resistance of the conductor if you have the proper equipment.

Which cables are affected?

The cables mainly affected are telephone cables - style CW1308, alarm cables and coaxial cables. Some manufacturers also offer Cat 5 and other data cables as CCA.

What risks are associated with CCA and CCS?

The main problems are that aluminum and steel have much higher resistance than copper. This leads to a reduction in current capacity resulting in overheating of the cable and possibly leading to a fire. Aluminum is also much more brittle than copper and this can lead to breakage during installation.

These cables are also prone to fatigue at the termination point which can cause random errors. This is especially true for insulation displacement connectors (ICDs). Alarm systems using CCA could lead to false readings and false alarms, while coaxial leads to degraded image quality, particularly at long distances.

Why is this a problem?

One of the difficulties is that even on close inspection it can be very difficult to detect CCA. As the wire is cut, there is a tendency for the copper to strike over the aluminum end, making it look like solid copper. Sometimes it is possible to tell with a magnifying glass or a simple burn test using a lighter. Aluminum has a higher melting point than copper, for example.

However, CCA should not simply be dismissed. Some applications, for short runs, for example, CCA could work to an acceptable standard. In this case make sure you know what you are buying and get significant cost savings. In some applications, the savings can be significant, while in others, the visits and customer dissatisfaction will be too great.

Conclusion

Talk to your supplier and make sure you know what is provided. Drag may not be a problem on short runs. In some cases the cost savings may be attractive, but make sure you consider the application and what the installation intends to achieve. If, like most users, you just want to 'set and forget', you might be better off sticking with pure copper conductors and taking advantage of their proper performance characteristics. Check the standard the cable must meet, if pure copper has been specified it has been for some reason, then you need to ask yourself if replacing CCA or CCS is a good idea.

Some suppliers clearly state CCA or CCS in their description, but if in doubt ask for a technical data sheet. If you are offered cheap cable you should be very careful if the description or spec sheet says CCA, CCS or Copper Alloy. Whichever you choose, make sure you know what you're buying - copper, aluminum copper or copper-clad steel. There is a big difference.