A: It depends on the application of the wire. Single-core wires are usually used in low-voltage electrical systems, such as household power supply systems, while multi-core wires are usually used in high-voltage electrical systems, such as power transmission systems. In some cases, multi-core wires can also be used in low-voltage systems, such as lamp control systems.

1, a single-core wire is a wire, in which there is only one metal conductor, and a multi-core wire is composed of multiple metal conductors, which can be a single wire or an insulating sheath composed of multiple wires.

2. Single-core wire has only one wire, so the current transmission capacity is small, and multi-core wire has multiple wires, so the current can be distributed among multiple wires, so the current transmission capacity is large.

3. Single-core wires are suitable for low-voltage electrical systems, such as household power supply systems, while multi-core wires are suitable for high-voltage electrical systems, such as power transmission systems.