Each component used in copper cable structures is crucial for transmitting signals and/or power to where they are needed. They can also affect safety, downtime, and installation.
When you want to transmit electricity or information from one place to another, whether you are sending data, video, audio, or control signals, the transmission process usually takes place over copper communication cables.
Copper cable is a market proven technology that enables reliable, cost-effective data and power transmission, while also being easy to terminate.
Each layer of copper cable structure is crucial for transmitting signals and/or power to where they are needed. These layers greatly affect the transmission of data and power over the entire lifecycle of the cable. They will also affect:
Safety during fire initiation and spread, as well as the amount and toxicity of smoke released
Shutdown time and system performance
Performance of cables in harsh environments
Convenience of cable installation
Each copper cable contains the following layers:
Conductor, capable of signal and/or power transmission
Insulation, protecting conductors and separating them from other conductors
Sheath, used to protect cables
According to the cable type, copper cables may also include the following layers:
Shielding can prevent interference that may disrupt signal transmission
Armor provides physical protection for the entire cable
Drainage line, used as a grounding path
Ground wire transfers current from the circuit to the ground
Each layer of high-performance cables is made of high-quality materials, which can improve safety and normal operation time. If you want to optimize the return on investment (ROI) of your system and technology, this level of performance is crucial.
Conductor: the center of everything
The conductor of a copper cable is located at the center of the cable and is protected by other layers. It transmits data signals and/or power from point A to point B.
Two types of conductors can be considered: solid conductors and stranded conductors. They differ in structure and performance.
A solid conductor is composed of a round wire, which has a low production cost and can be exposed or coated with metal. They are usually used for permanent applications because they are not easily bent. Solid conductors also carry more current than twisted wires of the same diameter.
Twisted conductors are made of twisted or braided copper wire bundles. Due to their structure, they have a longer bending life and the ability to withstand bending. Therefore, they are more flexible than solid conductors, making it easier for them to bypass obstacles and install in narrow spaces.
Insulation: protecting signal transmission
The inner insulation of the copper cable wrapped around the conductor is located between the conductor and the shielding layer (if any) or sheath. This type of insulation is called a "dielectric" on cables with high-frequency performance parameters.
It can protect conductors from environmental threats and current effects, and is a key part of ensuring high-frequency data transmission, playing an important role in preventing capacitor losses. It also separates conductors from each other to reduce electrical interference. It cannot prevent electromagnetic interference (EMI).
Copper cables use two types of insulation materials: thermoplastic (PVC, nylon, PE, PP, LSZH, etc.) and thermosetting (XLPE, EPR, etc.), also known as cross-linked materials. The installation location and operating environment of cables help determine the optimal insulation type.
The installation location and operating environment of cables help determine the optimal insulation type.
Compared to thermoplastic insulation, thermosetting insulation has a higher rated temperature. Therefore, it can resist cracking, wear, corrosion, and water, making it more durable.
Thermoplastic insulation will soften when heated.
Shielding: prevent interference
In copper cables, shielding is the metal layer surrounding the conductor. Not all copper cables have shielding. In order to optimize the effectiveness of the cable and ensure reliable signal transmission, it limits signal interference from external sources. It can also prevent cables from becoming interference sources for nearby systems or components. For copper cables carrying high-frequency signals or having multiple conductors, internal shielding and individual shielding will be used.
Two types of shielding can be considered for copper cables: foil shielding and braided shielding. Some cables use both types simultaneously to prevent low-frequency and high-frequency EMI.
Foil shielding is usually made of a thin and lightweight aluminum layer. Although copper foil is sometimes used, the price is relatively high. Belden uses aluminum and polyethylene compounds to improve durability. Compared to woven shielding, foil shielding is more cost-effective. They are most suitable for preventing RFI and EMI at higher frequencies.
Braided shielding is made by weaving copper or aluminum strands (depending on the cable) together to provide excellent mechanical strength and bending resistance. Braided shielding provides the best protection against low-frequency EMI.
Some cables use both types simultaneously to prevent low-frequency and high-frequency EMI.
Drain line: Ensure proper grounding of the shielding system
The shielded copper cable has a drainage line used to establish the correct grounding in the shielding system. In these cases, the discharge line completes the circuit from the shielding layer and transfers electrical noise from the circuit to ground. Drain lines are typically made of tin plated copper to ensure proper conductivity and corrosion resistance.
Whether copper cables need to be drained depends on factors such as the possibility of noise interference and whether the cable operates together with power lines or other EMI sources.
Ground wire: provides electrical safety
Some cables have grounding wires, which are specialized conductors that connect electrical systems to the ground and provide a safe dissipation path for excess electrical energy. For example, multi conductor cables sometimes use ground wires to minimize noise and improve signal quality to the greatest extent possible.
Armor: prevent physical damage to cables
Some copper cables have an additional protective layer called armor that wraps around the cable to prevent physical damage caused by compression or wear. Armor is usually made of steel or aluminum.
If copper cables are installed in harsh environments and may be physically damaged (such as being run over by forklifts, dropped by heavy objects, or bitten by rodents), then armor becomes the preferred option.
Sheath: Protects everything inside
There are several uses for cable sheaths. It can maintain the internal structure of the cable and protect it from environmental conditions. It also helps prevent the spread of fire and the release of smoke.
The sheath can prevent deterioration and damage, and provide buffering between the shield and external conductors.
The sheath can be designed to resist specific environmental factors such as oil, sunlight, or moisture, and has different levels of fire safety.
The cable sheath can also provide you with all information about the cable, including the installation location, manufacturer, and ease of operation (based on specifications and dimensions).
Similar to the insulation of copper cables, two main types of cable sheath materials can be considered:
Thermoplastic (PVC, FEP, LSZH, etc.)
Thermosetting (CPE, EPR, etc.)
The selection of cable sheath material should be based on the application and installation location of the cable.
Copper cables suitable for all types of connections
These seven layers must work together to create high-performance copper cables. Any inferior material will have a negative impact on the performance of your cables.
