Household electrical wiring is divided into hard and soft wiring. In daily life, there's also a distinction between strong and weak wiring. Weak wiring is common in every household, with the most common being network cables and telephone cables. Since these are essential and frequently used wiring, it's crucial to choose high-quality, premium cables when purchasing them. Below are tips for choosing network cables, telephone cables, HDMI cables, and surveillance cables.
A Brief Introduction to Weak Wiring
Weak wiring refers to signal and control cables with an operating voltage below 38V. Their most significant characteristics are low voltage resistance and poor current handling. Examples include communications and cable television cables.
Weak wiring includes network cables, telephone cables, HDMI cables, and surveillance cables.
Tips for Choosing Network, Telephone, HDMI, and Surveillance Cables
1. Choosing Network Cables
Common network cables used in local area networks include twisted pair, coaxial cable, and fiber optic cable. Twisted-pair cables are typically categorized by electrical performance: Category 3, Category 4, Category 5, Category 5e, Category 6, and Category 7. The higher the number, the newer the version, the more advanced the technology, the higher the bandwidth, and, of course, the higher the price. Current Category 5e and Category 6 unshielded twisted-pair cables easily provide 155Mbps communication bandwidth and have the potential to be upgraded to gigabit bandwidth, making them the preferred cables for horizontal cabling today.
Quality Identification
1. Category 3 cables have two pairs of four wires, while Category 5 cables have four pairs of eight wires.
2. The outer rubber coating of genuine cables is non-flammable, while that of dummy cables is often flammable.
3. The outer rubber coating of dummy cables softens at higher temperatures (above 40°C), while that of genuine cables does not.
4. The copper core of genuine cables is made of purer material, is softer, more resilient, and less susceptible to breaking.
5. Network cables are twisted counterclockwise, not clockwise. Clockwise winding will affect speed and transmission distance. 6. Shielded twisted-pair cables have a metal mesh and insulation between the conductors and the rubber. The connector is also covered with metal.
7. Use a magnet to identify iron-core cable. If a magnet attracts the cable (even slightly), it has an iron core and is not recommended.
8. Strip a small amount of the cable to check the core thickness. Thinner cores can also affect transmission efficiency. Therefore, choose a relatively thicker core.
II. Telephone Cable Selection
◇Material Selection
1. Copper-clad steel: This cable is relatively hard and not suitable for external wiring due to the risk of core breakage. However, it can be used buried in walls. It should only be used for short distances (for example, from a junction box in a hallway to a user).
2. Copper-clad aluminum: This cable is relatively soft and more prone to core breakage. It can be buried in walls or used for external wiring. It should only be used for short distances. (For example, from a corridor junction box to a user)
3. All-copper: This cable is flexible and can be buried in walls or run outside. It can be used for long-distance transmission. Only all-copper telephone cables meet national standards.
◇Quality Identification
1. Brands listed are trustworthy and their product quality is guaranteed.
2. Telephone cables made of imported high-purity oxygen-free copper conductors offer minimal transmission attenuation and signal loss, clear, noise-free sound, and a sense of distance during calls.
3. Telephone cables sheathed in high-grade transparent material are resistant to acid and alkali corrosion, age, and have a long service life.
4. Telephone cables sheathed in transparent material offer excellent mechanical, physical, electrical, and thermal stability, and contain very low levels of heavy metals and heavy metal compounds such as lead and cadmium.
5. Telephone cables made of imported polypropylene offer high purity, minimal transmission attenuation, and higher transmission speeds, making them suitable for broadband Internet access and capable of meeting the high transmission speed requirements of videophones.
2. Choosing an HDMI Cable
1. Determine the Interface Version
Different HDMI interfaces have different bandwidths and supported technologies. HDMI cables, like the HDMI interface, are available in versions 1.3 to 2.0, maintaining backward compatibility. Therefore, it's best to choose an HDMI cable that matches the HDMI interface version, or at least a higher version than the interface version.
2. Check the cable for certification marks
Check the product packaging for the HDMI or SIMPLAY certification logo. Good cables will have both certifications, ensuring their quality.
3. Check the cable connector
Gold-plated connectors on HDMI cables theoretically offer better corrosion resistance, conductivity, and high-temperature resistance, as well as ease of soldering. However, gold plating doesn't guarantee superior connector quality. Ultimately, it's the PIN pins within the HDMI connector that connect to the HDMI interface, making this the most important part of the cable. PIN pins are typically made of tin-bronze. Nickel is plated over the tin-bronze, making it easier to apply gold plating. Therefore, a well-made HDMI cable will have three layers of PIN pins.
4. Consider the cable's material and craftsmanship.
Traditional HDMI cables come in several different core materials. Generally, the best are pure copper or pure copper plated with silver. Pure copper ensures signal transmission quality and reduces signal interference and loss. Lower quality cables use alloys and iron as the core.
5. Avoid HDMI cables that are too thin.
The cable core material and shielding thickness significantly impact signal quality. Cables that are too thin often have reduced core and shielding, so be mindful of this.
3. Monitoring Cables
In the past two years, network cables have been frequently used for monitoring cables. Types of monitoring cables include 75-3, 75-4, and 75-5. These are single-axis cables with a central core and a high-strength braided mesh around the perimeter. When used as monitoring cables, the main cable is typically used as the main conductor, while the remaining braided mesh is soldered together.
The advantage of using network cables as monitoring cables is that they can be very long; typically, up to 300 meters is possible! Furthermore, if made of raw copper, the resistance is very low. Outdoor cables are typically used for this purpose because their sheath is very hard, making them ideal for cable pulling. Generally, the resistance of water-blocking cables should not exceed 80 ohms over a 300-meter length; this will not significantly affect the image quality.
It is generally recommended to use standard water-blocking cables or copper-clad silver water-blocking cables. Both of these cables can pass the FLUE4300 test, are very stable in quality, and have resistance values within the acceptable range.
The above has explained in great detail the purchasing tips for the four types of wires: network cables, telephone cables, HDMI cables, and monitoring cables. You can use this article as a reference when purchasing these four types of wires in the future. I believe you will be able to purchase more satisfactory wires.
