Cable selection is a very complicated process which depends mostly on these four key aspects:
While selecting a cable, the most important thing is to select the range of current that will be passing through the wire. The current moving through the cable increases the heat of the conducting cable. A comparative analysis of the heat vs the amount of current flow provides a better way to cable selection.
Voltage is among one of the important factors in cable selection. The maximum amount of voltage that could the cable could transfer is dependent on the thickness of the cable, insulating medium of the cable and the conductor size and types. But, unlike the current voltage value among the appliances remain the same throughout. It only differs when the voltage phase changes from single to three-phase. I-e in motors, generators, high-voltage transmission cables.
- Signal Frequency
Frequency is the rate at which a certain thing is repeated in a certain span of time. Frequency is different for every signal type, it could either be a direct current signal, alternating current signal or any other hybrid signal.
Signals with higher frequencies start to attenuate and the integrity of the signal dissipates due to a phenomenon named as ‘skin effect’. At higher frequency, the current is carried to the outer layer of the conductor instead of evenly moving throughout it. This reduces the cross-sectional area of the conductor inside the cable/wire. To counter this skin effect, instead of using a whole conductor inside the cable, a bundle of smaller wires is used.
- Temperature Rise
Temperature rise among the conductor is mainly due to the flow of current. But it also depends on the type of insulation and inappropriate method of temperature dissipation in the environment. If the surrounding does not allow proper discharge of the heat in the environment, the temperature of the cable’s conductor remain at high temperature and it damages the reliability of the cable.