The shielded wiring system originates from Europe. It adds a metal shield to the outside of the ordinary unshielded wiring system. It uses the reflection, absorption and skin effect of the metal shield to prevent electromagnetic interference and electromagnetic radiation. The shield system makes full use of the The balanced principle of the twisted pair and the shielding effect of the shielding layer thus have very good electromagnetic compatibility (EMC) characteristics. As we can see, most of the end users in Europe will choose to shield the cabling system.
At present, shielded wiring systems have been recognized by more and more users, and its good performance in electromagnetic compatibility is also being recognized by more and more people. Therefore, the shielded wiring products on the market are not limited to European products, and more and more manufacturers provide shielded wiring products. In the newly released North American TIA/EIA-568-B cabling standard, shielded and unshielded cables were simultaneously recommended as horizontal cabling, ending the history of unshielded systems in North America.
Common Shielding Questions and Answers Q: What is EMC?
A: EMC is electromagnetic compatibility. It means that an electronic device or network system has a certain ability to resist electromagnetic interference, and it cannot produce excessive electromagnetic radiation at the same time. In other words, it is required that the device or the network system can work normally in a relatively harsh electromagnetic environment, and at the same time there is the inability to radiate excessive electromagnetic waves to interfere with the normal operation of other devices and networks around.
Q: UTP cable is the ideal balanced transmission system. Why use FTP cable?
A: The UTP cable is twisted through the core to achieve EMC performance, which means that EMI is first received by the UTP cable before it is offset. However, as the frequency increases, UTP's EMC performance will decline. After measurement, it was found that the twisted pair of the cable can only meet the EMC performance of 30 MHz, and the twisted pair of higher electromagnetic interference will be powerless. So far, most of the actual network applications have operating frequencies below 30 MHz.
Also, the ideal balanced transmission system does not exist. The balance characteristics of UTP cables do not depend only on the quality of the parts themselves (eg twisted pairs) but are affected by the surrounding environment. Because the metal around the UTP, hidden "ground", traction in the construction, bending, etc. will destroy its balance characteristics, thereby reducing the EMC performance.
In fact, we usually install cables that will be threaded into metal conduits, plastic conduits, or other protections with different grounding impedances. Therefore, in order to achieve permanent ground performance, there is only one solution: ground all the cores with one more aluminum foil. Aluminum foil adds protection to the fragile twisted-pair core and creates a balanced environment for the UTP cable. This means that shielding solutions based on FTP cables are environment-independent, that is, independent of the environment. FTP is a blend of UTP's balancing features and construction flexibility and STP's shielding effect, which is the perfect combination of balancing and shielding principles.
Q: What is the shielding principle of FTP cable?
A: Different from the principle of balance cancellation in twisted pair, the FTP cable adds one or two layers of aluminum foil on the outside of the four twisted pairs, using the principle of reflection, absorption and skin effect of metal on the electromagnetic wave (the so-called skin effect is The distribution of conductors in the cross-section of the conductor tends to be distributed along the surface of the conductor as the frequency increases. The higher the frequency, the smaller the skin depth (ie, the higher the frequency, the weaker the penetrating ability of the electromagnetic wave). This effectively prevents external electromagnetic interference from entering. Cables also prevent internal signals from radiating and interfere with the operation of other equipment.
Experiments have shown that electromagnetic waves with a frequency exceeding 5 MHz can only pass through 38 μm thick aluminum foil.
If the thickness of the shielding layer exceeds 38μm, for example, the Nexans FTP cable shields two layers of aluminum foil with a thickness of 25μm, so that the frequency of electromagnetic interference that can enter the cable through the shielding layer is mainly below 5MHz. For the low-frequency interference below 5MHz, the double-twist principle can be effectively used to offset.
Q: How do we measure the performance difference between shielded and unshielded systems?
A: The advantage of the FTP cable shield system is that it provides better EMC performance than UTP cable. It is based on the isolation of the system from the external electromagnetic environment. Because the external electromagnetic environment will affect the entire wiring system data transmission. So far, there are no performance indicators or test methods to express or compare EMC performance. The good news is that the European Committee for Standardization CENELEC has started this work (Nikesen integrated wiring system is involved), and coupling attenuation is defined as an indicator of measuring EMC performance. This indicator is also written in the second edition of the international wiring standard ISO/IEC11801.
Nexans shielded wiring solutions
Nexans is the inventor of the FTP series cable and a leader in shielding technology. Its shielding products have been tested and certified by DELTA, the Danish independent electronic laboratory, UL of the US insurance laboratory, and the US ETL testing agency. The index of the series wiring products is much higher than the ISO/IEC11801, EIA/TIA568B and EN50173 standards.
The Nexans F2TP cable adopts the unique double-layered vertical aluminum foil shielding structure in the world. It consists of two layers of 25um thick aluminum foil wrapped outside the UTP cable. This double-layered vertical package structure can avoid the cable bending or heat shielding layer. The appearance of small gaps reduces the transfer impedance, improves the shielding effect, and makes the grounding (including shielded grounding and protective grounding) more convenient and reliable. This high-performance shielded cable is also very easy to install, its outer diameter is only 6.35 mm. For electromagnetic waves above 10 MHz, electromagnetic interference and electromagnetic radiation are counteracted by the mechanisms of reflection, absorption and skin effect of the shielding layer. The higher the frequency, the more obvious the effect of the shielding layer.
In view of electromagnetic compatibility (EMC), the shield of the cable must be in contact with a large area of ​​the metal surface, the so-called 360o grounding. In the Nexans double-layer aluminum foil shielding system, only one layer of the shielding layer is required to be stuck on the Nexans patented Clip-onTM cable lead frame to ensure that the shielded cable is grounded 360° around the distribution frame and the information socket. (Grounding), there is absolutely no so-called "antenna effect." This Clip-onTM cable leadframe is integrated with the modular distribution panel.
At present, shielded wiring systems have been recognized by more and more users, and its good performance in electromagnetic compatibility is also being recognized by more and more people. Therefore, the shielded wiring products on the market are not limited to European products, and more and more manufacturers provide shielded wiring products. In the newly released North American TIA/EIA-568-B cabling standard, shielded and unshielded cables were simultaneously recommended as horizontal cabling, ending the history of unshielded systems in North America.
Common Shielding Questions and Answers Q: What is EMC?
A: EMC is electromagnetic compatibility. It means that an electronic device or network system has a certain ability to resist electromagnetic interference, and it cannot produce excessive electromagnetic radiation at the same time. In other words, it is required that the device or the network system can work normally in a relatively harsh electromagnetic environment, and at the same time there is the inability to radiate excessive electromagnetic waves to interfere with the normal operation of other devices and networks around.
Q: UTP cable is the ideal balanced transmission system. Why use FTP cable?
A: The UTP cable is twisted through the core to achieve EMC performance, which means that EMI is first received by the UTP cable before it is offset. However, as the frequency increases, UTP's EMC performance will decline. After measurement, it was found that the twisted pair of the cable can only meet the EMC performance of 30 MHz, and the twisted pair of higher electromagnetic interference will be powerless. So far, most of the actual network applications have operating frequencies below 30 MHz.
Also, the ideal balanced transmission system does not exist. The balance characteristics of UTP cables do not depend only on the quality of the parts themselves (eg twisted pairs) but are affected by the surrounding environment. Because the metal around the UTP, hidden "ground", traction in the construction, bending, etc. will destroy its balance characteristics, thereby reducing the EMC performance.
In fact, we usually install cables that will be threaded into metal conduits, plastic conduits, or other protections with different grounding impedances. Therefore, in order to achieve permanent ground performance, there is only one solution: ground all the cores with one more aluminum foil. Aluminum foil adds protection to the fragile twisted-pair core and creates a balanced environment for the UTP cable. This means that shielding solutions based on FTP cables are environment-independent, that is, independent of the environment. FTP is a blend of UTP's balancing features and construction flexibility and STP's shielding effect, which is the perfect combination of balancing and shielding principles.
Q: What is the shielding principle of FTP cable?
A: Different from the principle of balance cancellation in twisted pair, the FTP cable adds one or two layers of aluminum foil on the outside of the four twisted pairs, using the principle of reflection, absorption and skin effect of metal on the electromagnetic wave (the so-called skin effect is The distribution of conductors in the cross-section of the conductor tends to be distributed along the surface of the conductor as the frequency increases. The higher the frequency, the smaller the skin depth (ie, the higher the frequency, the weaker the penetrating ability of the electromagnetic wave). This effectively prevents external electromagnetic interference from entering. Cables also prevent internal signals from radiating and interfere with the operation of other equipment.
Experiments have shown that electromagnetic waves with a frequency exceeding 5 MHz can only pass through 38 μm thick aluminum foil.
If the thickness of the shielding layer exceeds 38μm, for example, the Nexans FTP cable shields two layers of aluminum foil with a thickness of 25μm, so that the frequency of electromagnetic interference that can enter the cable through the shielding layer is mainly below 5MHz. For the low-frequency interference below 5MHz, the double-twist principle can be effectively used to offset.
Q: How do we measure the performance difference between shielded and unshielded systems?
A: The advantage of the FTP cable shield system is that it provides better EMC performance than UTP cable. It is based on the isolation of the system from the external electromagnetic environment. Because the external electromagnetic environment will affect the entire wiring system data transmission. So far, there are no performance indicators or test methods to express or compare EMC performance. The good news is that the European Committee for Standardization CENELEC has started this work (Nikesen integrated wiring system is involved), and coupling attenuation is defined as an indicator of measuring EMC performance. This indicator is also written in the second edition of the international wiring standard ISO/IEC11801.
Nexans shielded wiring solutions
Nexans is the inventor of the FTP series cable and a leader in shielding technology. Its shielding products have been tested and certified by DELTA, the Danish independent electronic laboratory, UL of the US insurance laboratory, and the US ETL testing agency. The index of the series wiring products is much higher than the ISO/IEC11801, EIA/TIA568B and EN50173 standards.
The Nexans F2TP cable adopts the unique double-layered vertical aluminum foil shielding structure in the world. It consists of two layers of 25um thick aluminum foil wrapped outside the UTP cable. This double-layered vertical package structure can avoid the cable bending or heat shielding layer. The appearance of small gaps reduces the transfer impedance, improves the shielding effect, and makes the grounding (including shielded grounding and protective grounding) more convenient and reliable. This high-performance shielded cable is also very easy to install, its outer diameter is only 6.35 mm. For electromagnetic waves above 10 MHz, electromagnetic interference and electromagnetic radiation are counteracted by the mechanisms of reflection, absorption and skin effect of the shielding layer. The higher the frequency, the more obvious the effect of the shielding layer.
In view of electromagnetic compatibility (EMC), the shield of the cable must be in contact with a large area of ​​the metal surface, the so-called 360o grounding. In the Nexans double-layer aluminum foil shielding system, only one layer of the shielding layer is required to be stuck on the Nexans patented Clip-onTM cable lead frame to ensure that the shielded cable is grounded 360° around the distribution frame and the information socket. (Grounding), there is absolutely no so-called "antenna effect." This Clip-onTM cable leadframe is integrated with the modular distribution panel.
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1.Waterproof, tide proof, air proof and non-poisonous resealable plastic pouch
2. Available in customers' designs, size range: 4(width)×6(length)cm to 40(width)×50(length)cm.
3. Used to pack food, medicine, medical apparatus, electronic products, cosmetic, handicraft.
4. Good service and reasonable price
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Yong Yue Medical Technology(Kunshan) Co.,Ltd , https://www.yonyuetip.nl