What are the differences between multicore cable and single core electrical cable?
The main difference between single core electrical cable and multicore cables is the difference in the flexibility of the wires. According to the different environments in which they are used, different types of wires and cables are selected.
What is a single core electrical cable?
Single core electrical cable wire, low resistance, carrying capacity greater than multi-strand copper core wire, general lighting and socket wires should be 2.5 square millimeters, empty call wires should not be less than 4 square millimeters, wiring wires should be green and yellow double-colored wires, and the switch wires should be connected to live wires Any one of red, white, black, purple, etc. Single-strand wires are mostly double-plastic insulation, and hard wires are mostly single-strand wires, which are generally used for large currents; the texture is relatively hard.
Single core wire is also called BV wire
BV: Copper core PVC insulated wire, which is our commonly used single core copper wire. BV wire has only one conductor in one insulating layer.
Commonly used BV wire colors are: red, yellow, blue, green, black, white, two-color yellow, green, brown.
Advantages: The advantage of single core electrical cable wire is that it is very convenient when threading. Many electricians like to use single core electrical cable wire to lay circuits, and the stability of single core electrical cable wire will be better.
Disadvantages: The heat dissipation function is relatively poor, because it has only one wire, so it is easy to be bent.
What is a multicore cable wire?
Multicore cable wires are generally three-core wires. Usually, three-core wires are grounded at both ends, because in the execution of the cable, the sum of the currents flowing through the three cores is zero, and the two ends of the metal shielding layer of the cable are basically grounded. There is no induced voltage. Generally, cables with a voltage level of 35kV and below.
Multicore cable wire is also called BVR wire
BVR: Copper core PVC insulated flexible wire, which is the multi-strand copper wire we commonly use.
Generally can be divided into red, yellow, blue, green, black, white, double a total of seven colors
Advantages: Its flexibility is still very good. Compared with single-core wires, the heat dissipation function is stronger, and the load current of this wire is relatively large, and the power is also relatively strong.
Disadvantages: There are many connectors of multi-core wires, so it must be handled properly, otherwise it is easy to have line problems later.
The difference between single core electrical cable wire and multicore cable wire
1. Different construction
Single core electrical cable generally have a voltage level of 35kV and above, and generally cannot be directly grounded at both ends. The two ends of the single core electrical cable are directly grounded, and the metal shielding layer of the cable may also generate circulating current. According to related reports, the circulating current generated by the grounding of both ends of the single core electrical cable can reach 30%-80% of the normal transmission current of the cable core, which reduces The current carrying capacity of the cable is increased, the electric energy is wasted to cause loss, and the cable insulation aging is accelerated, so the ssingle core electrical cable should not be grounded at both ends.
A multicore cable is a cable with multiple conductors that are insulated from each other in the outer insulation layer of the cable. Multi-core wires are generally three-core wires. During the installation process, the core wire ends that need to be stripped of the insulation layer are spread out and straightened, and then the core wires close to the 1/3 line section of the insulation layer are twisted tightly, and then the remaining 2/3 The 3-core wire ends are spread out into umbrellas, and each core wire is straightened. Because the sum of the currents flowing through the three cores is zero during the operation of the cable, there is basically no induced voltage at both ends of the cable metal shielding layer. When the current is large, the required cable is relatively thick, and it is more suitable to use multicore cable at this time.
2. Different applicability
If you need to lay mobile lines, it is best to choose multicore cable wires. If it is a long-distance laying, it is best to choose a single core electrical cable wire, so as to ensure that it is not easy to be damaged during wiring.
3. Different laying methods
Multicore cable wires generally need crimping or welding lugs, especially BVR wires below 4 square meters; while single-strand copper wires are more convenient in terms of line connectors and equipment wiring.
4. Different uses
Single core electrical cable wires are durable and have good electrical conductivity, and are suitable for fixed installation of strong electricity indoors, such as fixed wiring on walls; multi-core copper wires are flexible and easy to lay through pipes, and are suitable for laying in movable places, such as chandeliers, etc. The use of weak current.
5. In terms of price: in the case of the same cross-sectional area. The current carrying capacity of multicore is higher than that of single core. Because the current has skin effect. What is going is the surface of the conductor. Multi-cores have a larger unfolded surface area. therefore. The carrying capacity is larger than that of the core. And the heat dissipation performance is also better. Of course, the price of multicore cable wire is also more expensive.