What core thickness in cables is usual?

The thickness of the cores in cables is crucial. If you send too much current through a cable that is too thin, you will get overheating, with all the consequences that entails.

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Cable thickness factors

The current expressed in amperes determines the minimum thickness of the cable. The current is determined by the power consumption of the connected devices. Current flowing through a cable encounters resistance. The longer and thinner the cable, the more resistance the current encounters.

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Other factors that are important for the vein diameter are

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'Fusing' the installation cable:
'Fusing' the installation cable to a certain number of amperes (A) and voltage (V) is important because this can keep the cable undamaged after a short circuit or overload. The higher the current through the cable, the thicker the core must be. A thick core can simply handle more current and thus prevents overheating.

Voltage drop:
Because every cable has an electrical resistance (expressed in 'Ohm'), voltage loss occurs. This happens with every installation cable. The longer the cable, the higher the voltage loss and resistance. When cables are thicker, the electrical resistance is lower. You can also reduce resistance by choosing copper instead of aluminum. Copper has a lower resistance than aluminum. According to the official rules of the NEN1010, the installation cable may not have more than 5% voltage loss.

Temperature of the environment:
When the ambient temperature of the cable increases, the temperature of the cable will logically also increase. And the warmer the cable, the higher the voltage drop. A YMvK installation cable has a maximum temperature under which it still functions well, namely 90 degrees. When a cable is going to be used in a warm environment, you can take this into account by using a thicker cable. This prevents overheating.

Amount of installation cables in a cable duct:
The more cables there are in a cable duct, the greater the heat development can be, because cables heat each other up. The insulation around the cable is important for the temperature of the cables. Certain insulation materials are more resistant to higher temperatures. Check the specifications of the cables for this. Depending on the cable thickness and the insulation of those cables, you can place approximately 8 cables in one cable duct.

Short circuit current:
The thickness of a conductor must be adjusted to the expected duration of a short circuit. If a short circuit current can be interrupted quickly, you can use thinner cables. If the short circuit current lasts longer, you must use thicker cables. In addition, a short circuit current can cause forces on the cable. A thick cable can better handle these forces that are released and a thicker cable is better able to withstand the heat that a short circuit current can generate.

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What core thickness do I need?