Almost every utility and industry relies on an elaborate system of power cables. With time most of these systems age and experience failures on several grounds, so understanding the root cause of power cable accessories failures is crucial to maintain low operating costs and have reliable operations.
Finding the root cost of power cable accessories failure will also help in establishing preventive measures. Power cable accessories might cause trouble due to insulation failure or local overheating. To have a systematic approach towards such cable failures, we will look into different cable accessories and the reasons for their failure. Let’s get rolling!
Component Of Power Cables
It is important to familiarize with the components of cables for a better understanding of power cable failures and their root causes:
Electric Conductor: it is the wire that channels the flow of power.
Cable Metal Protection: it protects the power cable and ensures longevity.
Insulation: insulation materials like PVC and rubber cover the electric wires and contain the current within the conductor.
Outer Sheath: it is a final covering protecting all the other three components mentioned above.
Different Types Of Power Cable Accessories
1 – Duct Seals: it provides a defensive water-tight seal to the cable to protect it from flood and fire spread. It is used in all low, medium, and high voltage cables for protection.
2 – Hardware, Grounding & Mounting: cables are grounded to avoid electric shocks and accidents. Cable grounding gives the electric charges a space to reside. Cable mounts are used to provide support to the cable wires.
3 – Joints & Splices: a cable consists of joints and splices that are joints/junctions at points where two wires connect.
4 – Potting Resin: it is a gel-like liquid used to fill the empty spaces in the electronic assembly to avoid shocks, water, and corrosive agents.
5 – Heat Shrinkable Anti Tracking Power Cable Breakouts: These are vital power cable accessories that give excellent UV resistance, weather resistance and are anti-tracking.
6 – Power Cable End Caps: These caps are used to cover the unused power cable ends, especially when there is a live cable nearby.
7 – Heat Shrinkable Insulating Power Cable Wraps Around Sleeve:These are mesh-like coverings that can be used to pack your multiple cable wires into one tube for better organization.
8 – Heat Shrinkable Anti Tracking Tubing: power cables are shielded against chemical pollution and tracking with the help of anti-tracking tubes.
9 – Separable Connectors: made up of rubber or silicon, a separable connector ensures the longevity of power cables.
10 – Heat Shrinkable Bus Bar Insulation Tubing: insulation tubes curb heat transfer and provide a barrier against moisture, thus increasing thermal efficiency.
Detailed analysis shows the following reasons for failures of Power Cable Accessories:
Now that we have discussed all the components of power cables and the various accessories, it’s time to identify different reasons for power cable accessories failures.
1 – UV Exposure: cables that are not UV rays resistant develop cracks on being exposed to UV rays, thus leading to cable failure. Make sure to use a UV light resistant material for your power cables.
2 – Rodent Attack: this is a very common reason behind the failure of power cables. The rodents damage the outer covering of the cable, which can lead to serious consequences like electric fire if left unnoticed.
3 – Errors In Installation Process/Standards: if an error occurs during installation or the person installing power cables isn’t an expert, there might be a problem later due to the wrong configuration and mishandling.
4 – Design Issues: if the makeover of power cable accessories isn’t right, the material used is cheap, or there is a manufacturing fault, it will lead to a cable failure. Always buy a good quality product that promises longevity.
5 – Dielectric Breakdown: when the power cable is subjected to a very high voltage, the insulation sheath also turns into a conductor and starts to carry current, ultimately damaging the cable and leading to sparks.
6 – Ageing: electric cables degrade with time. Aging accelerates if the cable isn’t used under optimal conditions. A good cable can be expected to last for up to 25 years. Do a regular check-up to avoid accidents due to power cable failure.
7 – Corrosion: if the accessories used are exposed to moisture or water, the conductors will develop rust which will result in short circuits and poor performance.
8 – Environment: if a cable or accessories that are not robust enough for the tough environment are used, they are likely to fail. It is recommended to choose power cables and accessories according to the needs of the environment. For example- if the power cable is in an open area and receives a large amount of sun exposure, use a cable that is UV resistant .
9 – Overheat: excessive heating of electric wire damages insulation and sheath material, thus causing power cable failure.
10 – Overload: if the cable wire is used under voltage higher than its maximum capacity, the power cable will degrade and bring electric fire and sparks.
11 – Contamination: the other reasons for power cable failure can be contamination through cold, intense heat, chemicals, gases, or unfavourable weather conditions.
12 – Poor Maintenance: nothing can last long without proper care and maintenance. Make sure to check your electric cables frequently to keep problems and damages at bay. Also, set up preventive measures and take instant actions if you find damage.
Power cables can fail due to the wide reasons mentioned above; however, the weakest links of cables are the joints and terminations. They are vulnerable to damages during service due to numerous factors like stress, aging, and corrosion. Before installing cables, verify the quality of power cable accessories and other aspects to secure the longevity and optimum performance of the power cables.