What is the difference between single core cable and multi-core cable?

Single core or multi-core
Multi core cable or single core cable is better. The difference between single core cable and multi-core cable. Power cables are generally divided into single core, double core and three core cables. Single core cable refers to that there is only one conductor in one insulation layer, while double core cable refers to that there are two conductors in one insulation layer. In fact, these two kinds of cables have their own advantages and disadvantages. For example, when the line of single core cable is long, the control circuit with large electric flow in work or when laying in water, in order to prevent or reduce the positive and intermediate connectors, or when the single core cable has a good comprehensive safety project than the multi-core cable, the single core cable can be used.


Is multi-core cable better or single core cable better
From the perspective of current, the current passing through multi-core cables with the same cross-sectional area is relatively larger and the load is larger than that of single core cables.
From the perspective of power loss, the two ends of a single core cable are directly grounded, and the metal shielding layer of the cable may also generate circulating current, which can reach the current carrying capacity of the cable, and waste electric energy to form a loss. Multi core wires are generally three core wires, because in the operation of the cable, the total current flowing through the three cores is zero, and there is basically no induced voltage at both ends of the metal shielding layer of the cable.
In terms of cost, among wires with the same cross-sectional area, the cost of single core cables is cheaper than that of multi-core cables, which are slightly more expensive.


From the perspective of installation, the single core wire appears to be hard when threading the pipe, while the multi-core wire should be softer and easier to wire.
Difference between single core cable and multi-core cable
2-core cable: when the neutral line of 1kV and below switching power supply is immediately grounded, the number of cable cores of single-phase electrical control circuit should be 2-core cable when the maintenance line and neutral point share the same electrical conductor. The control circuit of DC power supply system can be used, and 2-core cable should be selected.
3-core cable: when 1kV and the following switching power supply neutral line are immediately grounded, the number of AAAC Cable cores of single-phase electric control circuit is: when the maintenance line and neutral point are separate, 3-core cable should be selected.
4-core cable: 1kV and below 4-core cable (3+1 cable), in which the fourth core is not only used as grounding protection, but also to transport the unbalanced current and short-circuit capacity of the power supply system. Its size is determined by the unbalanced current and short-circuit capacity, but generally not less than 1/2 of the phase line.
5-core cable: 1kV and the following three-phase four wire distribution room system software, some power distribution equipment routes of electrical devices with high safety coefficient, and some communication management centers and automatic machinery that need to ensure power safety and anti-interference grounding devices, it is advisable to choose TN-C distribution room system software of 5-core cable, so that the maintenance line (PE line) and neutral point (PN line) are independent, The cross section of cable core is generally 3 large, 2 small, 4 large, 1 small or 5 large.
The difference between 4-core cable and 3+1-core cable: for 1kV and the following three-phase four wire distribution room system software, when the maintenance line and neutral point share the same electrical conductor, 4-core cable should be selected instead of the method of 3-core cable plus single core cable to form a loop, and the method of using the metal protective sleeve or armored cable layer of 3-core cable as the neutral point immediately. Otherwise, when the 3-phase current is unbalanced, it is equivalent to the operation of a single core cable, which is very easy to cause DC impact.
The above is the difference between single core cable and multi-core cable, for reference only. I believe you have understood the differences and advantages of the two. There is no absolute statement, which needs to be judged according to the specific use environment! Multi core cable has good high-frequency performance, flexibility and easy construction wiring, but the price is high, and the cost of single core cable is low. Single core cable will also be used in specific environments

Choose Language