I understand that telecommunication cables are often twisted to cancel out electromagnetic interference (EMI) from external sources, e.g., crosstalk.
Are power cables ever twisted and if so, why?
Electronic – Line or Low or High Voltage Twisted Cable
cablespower supply
Best Answer
Power cables are twisted for a variety of reasons; one important example is the power wiring that delivers AC from a pole-top transformer to your home. There is one high-tensile (steel or aluminum) cable that anchors the conductors, and twisting the conductors around that cable keeps them from drooping and stretching under tension.
Flexible power cables are usually twisted insulated conductors inside a round sheath, which acts to equalize any tension that might act on the cable: the wire path is not a straight line, so pulling on the cable doesn't stretch any of the wires, just stretches the sheath (and the cables inside become more or less straightened until the tension is relieved).
When a power cable is twisted, look for a mechanical reason, not electromagnetic interference.