In a nutshell, if you purchased a cable that is manufactured to international standards, and wired indoors according to proper guidelines, your cables are generally expected to last based on a design life of at least 20-30 years.
What could affect the actual cable’s lifespan?
There are however, many operational and environmental factors that would affect the actual lifespan of a cable. These include:
Overload or short circuit events which would cause shortening of cable life.
Whether the cable is near high heat sources (eg. installed at a high ambient temperature that was not factored in prior, or is placed next to other circuits that were not accounted for during cable sizing).
Whether the cable is exposed to outdoor elements such as UV radiation or weather conditions that was not a part of the original design. Or if water has reached the cable core. Or if there is an unforeseen pest attack.
Presence of contaminants, oil, or acids that could degrade the sheath or insulation.
If the cables are subjected to mechanical stress, such as tensile, vibration, or bending, that could occur during or post installation.
Thanks to international bodies such as IEC, BS EN, or national standards like SS (Singapore Standards), cable standards have been developed to test for performance in various cable applications. While standards do not specify the life expectancy of a manufactured cable, these standards include electrical tests and non-electrical tests that would overall allow a cable lifespan of at least 20-30 years under typical indoor use. So end users can have a peace of mind on the cable's service life when purchasing cables that come with Certificate of Compliance to the appropriate national or international standards.
To ensure optimal electrical cable lifespan, it is also important to minimize the influence of the operational and environmental factors stated above. Choosing the most suitable insulation and sheath material according to the cable application, as well as the sizing the cable correctly would be key.
Check out our one-page properties table for common cable insulation and sheath materials: PVC, XLPE, LSZH, EPR. The table includes data such as tensile strength, elongation, and dielectric constant that could address some of the factors above when designing your cabling system.
Feel free to contact us for any cable selection requirements.