Detailed Comparison and Introduction of BV Wire and BVR Wire

2025-08-22 00:48:35

1. Structural Features

• BV Wire: It is a single-core hard conductor non-Sheathed Cable, whose conductor is composed of a solid Copper Wire. The diameter of this copper wire is relatively thick, so the overall wire is hard in texture, not easy to be bent at will, and has strong shape retention. The insulation layer is usually made of polyvinyl chloride (PVC) material, which is wrapped around the copper wire to play the role of insulation and protection.

• BVR wire: It is a Multi-Core soft conductor Non-sheathed Cable, and the conductor is made of multiple thin copper wires stranded together. Generally speaking, the number of copper wires varies according to the wire diameter, ranging from dozens to hundreds. Due to the stranding of multiple thin copper wires, the overall texture of the wire is soft, with good Flexibility, and can be bent many times without being easily damaged. The insulation layer is also mostly polyvinyl chloride.

2. Performance

• Current-carrying capacity: Under the same cross-sectional area, the current-carrying capacity of BVR wire is slightly higher than that of BV wire. This is because the multi-strand structure of BVR wire makes the contact area between the conductor and air larger, and the heat dissipation performance is better, which can quickly dissipate the heat generated during work, thus improving the current-carrying capacity to a certain extent. For example, a 2.5 square millimeter BV wire has a safe current-carrying capacity of about 25A, while the safe current-carrying capacity of a BVR wire of the same specification can reach about 28A (the specific value will vary slightly due to factors such as the laying environment).

• Mechanical performance: BV wire has high hardness and strong tensile strength, but poor flexibility, and repeated bending is easy to cause conductor breakage; BVR wire has excellent flexibility, can adapt to complex laying paths, has strong bending resistance, but relatively weak tensile strength, so it is necessary to avoid excessive pulling during construction.

3. Construction and Installation

• BV wire: Due to its relatively hard texture, it is more convenient to lay in straight paths, and it is not easy to entangle during laying. When connecting joints, the operation is relatively simple. Usually, the insulation layer is stripped, then directly tightened, and then wrapped with insulating tape. However, it is necessary to pay attention to the tightening force to ensure good contact. However, when it is necessary to pass through pipes with many bends or narrow spaces, the construction of BV wire is more difficult, and it is easy to get stuck in the pipe or cause wear of the insulation layer.

• BVR wire: The feature of good flexibility makes it perform well in complex path laying, and can easily pass through curved pipes and narrow spaces. But because it is stranded by multiple copper wires, the joint treatment is relatively complicated. If it is directly tightened, poor contact may occur due to scattered copper wires, resulting in heat generation. Therefore, the joints of BVR wires usually need to be crimped with terminals or welded to ensure good conductivity and connection stability.

4. Application Scenarios

• BV wire: It is often used in fixed laying electrical lines, such as pre-embedded lines in building walls, household lighting circuits, socket circuits, etc. In these scenarios, once the lines are laid, they rarely move or bend, and the hard characteristics of BV wire can meet the needs of long-term stable operation.

• BVR wire: It is suitable for occasions that need frequent movement, bending or vibration. For example, the Internal Wiring of distribution boxes and switch cabinets, because the internal space is limited and the line layout is complex, the wires need to have good flexibility; the lead wires of motors, because the motor will vibrate when working, and BVR wire can adapt to this vibration without being easily damaged; in addition, BVR wire is also often used in some temporary power supply lines or power supply lines of mobile equipment.

5. Price and Cost

• BV wire: The production process is relatively simple, just wrap the insulation layer around a single copper wire, so the production cost is low, and the market price is relatively cheap.

• BVR wire: In the production process, multiple thin copper wires need to be stranded, and then wrapped with an insulation layer. There are more process steps, and higher requirements for the uniformity of stranding, which leads to an increase in production cost. The price is higher than that of BV wire of the same specification, and the price per meter is generally 10%-20% higher.

6. Service Life and Maintenance

• BV wire: It has a long service life when laid fixed and not bent by external forces. However, if it is in an environment with frequent vibration or needs to be bent repeatedly for a long time, it is easy to have problems such as insulation layer cracking and conductor breakage, and the maintenance cost is relatively high.

• BVR wire: Due to its good flexibility, its service life in vibration and bending environments is longer than that of BV wire, and it is not easy to have faults caused by mechanical damage. It is relatively easy to maintain, which can reduce the later maintenance workload.