How to choose the right household wire?
In fact, you only need to look at the three parts of the wire safety sign, the insulation layer, and the core conductor when purchasing wires. If there is no problem with these three parts, it is a reliable and good wire.
Qualified Cable Product Specifications
1. Safety signs
(1) Complete qualification package:
Electricity safety is very important, so the wires must be produced by regular manufacturers with guaranteed quality. From the packaging point of view, there must be a complete certificate of conformity, which should include complete information such as specifications, implementation dimensions, rated voltage, length, date, factory name and address. In addition, roller packaging can reduce the abrasion of the insulation layer during production, transportation and handling, and it is also convenient for electricians to install.
(2) Excellent internal and external materials:
Outer insulating layer material: The insulating layer on the outside of the wire is the outer layer insulation, which can help prevent electric leakage, short circuit, electric shock and other accidents caused by the contact between the conductor and the outside world. The material of the insulating layer is resin, plastic, silicone rubber, PVC, etc.
The inner core of the wire is also an important structure of the wire. Generally, the inner core of the wire is made of copper. A good copper core has a purplish-red luster and is soft to the touch. The inferior copper core is yellowish or white, or appears purple-black.
(3) Weight of wire:
Good quality wires are generally within the specified weight range. For example, the commonly used plastic insulated single-strand copper core wire with a cross-sectional area of 1.5mm2 has a weight of 1.8-1.9kg per 100m.
2. Insulation layer
The layer of rubber on the outside of the wire is the insulation layer of the wire. Its existence can not only prevent external factors from causing damage to the conductor (protective conductor), but also protect the conductor from causing damage to the outside world (insulation, flame retardant) after a fault occurs. To judge the quality of the insulating layer, the following three methods can generally be used:
(1) The appearance is smooth and the resilience is high:
Gently stroke the surface of the insulating layer with your hand, if the surface is rough, it proves that the production process of the insulating layer is poor, and faults such as leakage are prone to occur. Press the insulating layer with your fingernail, if it can rebound quickly, it proves that the insulating layer has high thickness and good toughness.
(2) Good bending toughness:
Take a piece of wire, bend it back and forth several times, and then straighten the wire to observe. If there are no traces on the surface of the wire, it proves that the wire has good toughness. If there are indentations and serious whitening on the surface of the wire, it proves that the toughness of the wire is poor. Over time, the insulating layer will age and leak electricity.
(3) The insulating layer is not easy to burn:
Keep burning the wire with the lighter until the wire insulation catches fire. Then turn off the lighter and start timing. If the wire can be automatically extinguished within 5 seconds, it proves that the wire has good flame retardancy. Otherwise, it proves that the flame retardant ability of the wire does not meet the standard, and the circuit is overloaded or the circuit is prone to fire.
3. Core conductor
(1) Look at the color of the copper core:
Although they are all called "copper", some conductors contain impurities more or less. The more impurities it contains, the less conductive the conductor is. The amount of impurities contained in the conductor is generally expressed in the color. High-quality copper is called "red copper" or "red copper" - the copper core of qualified copper core wire should be purple-red, shiny, and soft to the touch. The copper core of the copper core wire is yellowish or white, and the whiteness in the yellow is a reflection of low-quality copper. The worse the copper, the lighter the color and the more yellow it is called "brass". Some of the copper is yellowish - this copper is already very high in impurities.
(2) Thickness of wire core:
We must first choose the color. Between the same colors, we can judge which is better or worse by comparing the thickness. When the color conflicts with the thickness, we should choose the color first (such as the difference between the thinner red copper and the thicker brass). time, preference is given to red copper).
When the wire is the same, the thicker it is, the stronger the conductivity. When comparing the thickness, only the conductor should be compared, and the thickness of the insulating layer should not be added.
(3) The length of the wire:
The regular national standard quality building household wires are 100 meters per roll, while the inferior wires are mostly 85 meters, 90 meters, and 95 meters. In fact, they do not meet the standard. In the relevant scales, the error of the length of the wires cannot exceed 2%. The diameter of the section wire should not exceed 0.02%. There are a lot of short-term lengths and falsification in the section (for example, the line marked with a section of 2.5 square millimeters is actually only 2 square millimeters thick).
(4) Whether the core is located in the middle of the insulating layer:
What's not in the center is the eccentric phenomenon caused by the low craftsmanship. If the power is low during use, it can be peaceful. Once the power consumption is large, the thinner side is likely to be broken down by the current. It is advisable to take a wire end and bend it repeatedly by hand. Those with soft hand feel, good fatigue resistance, plastic or rubber feel elastic and no cracks on the wire insulator are superior products. The outer plastic skin of the wire should be bright and fine in texture, and there should be no open flame when ignited with a lighter.
Regular wire insulation is uniform in thickness, not eccentric, and tightly wrapped around the conductor. It should be noted that some inferior insulating layers are made of recycled plastic. As long as you squeeze a little harder, the squeezed place will turn white and powder will fall.
What are the common classifications of household wires？
The types of household electric wires are mainly classified according to the use and the wire core. According to the wire core, they can be divided into BV, BVR, RV, BVVB, and RVV. Their materials and compositions are different, so the use is more bare wire, The difference between insulated wires, heat-resistant wires, shielded wires, power cables, control cables, communication cables, radio frequency cables, etc.
1. BV: It is a single core wire of copper wire, which is relatively hard, also called hard wire.
2. BVR: It is a single-core wire with many strands of copper wires twisted together, also called a flexible wire.
3. RV: It is also a soft wire. It is a single-core wire with more strands of copper wires twisted together. It is generally not used for home improvement.
4. BVVB: It is a hard sheathed wire, that is, two or three BV wires are sheathed together.
5. RVV: It is a soft sheathed wire, that is, two, three or four RV wires are sheathed together.
The above is how to correctly choose household wires, and what are the common classifications of household wires. I hope it can help you understand the relevant knowledge of household wires. Zhengzhou Jinshui Cable Group has always provided you with the best quality f