>>U/UTP twisted pair: commonly referred to as UTP twisted pair, unshielded twisted pair.
>>F/UTP twisted pair: a shielded twisted pair with a total shield of aluminium foil and no pair shield.
>>U/FTP twisted pair: shielded twisted pair with no overall shield and an aluminium foil shield for the pair shield.
>>SF/UTP twisted pair: double shielded twisted pair with braid + aluminium foil as total shield and no shield on the pair.
>>S/FTP twisted pair: double shielded twisted pair with braided total shield and aluminium foil shield for pair shielding.
1. F/UTP shielded twisted pair
Aluminum foil total shielding shielded twisted pair (F/UTP) is the most traditional shielded twisted pair, mainly used to isolate the 8-core twisted pair from external electromagnetic fields, and has no effect on electromagnetic interference between pairs.
The F/UTP twisted pair is wrapped with a layer of aluminium foil on the outer layer of the 8 core twisted pair. That is, outside the 8 cores and inside the sheath there is a layer of aluminium foil and a grounding conductor is laid on the conductive surface of the aluminium foil.
F/UTP twisted-pair cables are mainly used in Category 5, Super Category 5 and Category 6 applications.
F/UTP shielded twisted pair cables have the following engineering features.
>> the outer diameter of the twisted pair is larger than that of an unshielded twisted pair of the same class.
>>not both sides of the aluminium foil are conductive, but usually only one side is conductive (i.e. the side connected to the earth conductor)
>> the aluminium foil layer is easily torn when there are gaps.
Therefore, the following issues should be taken into account during construction.
>> that the aluminium foil layer is terminated to the shielding layer of the shielding module together with the earthing conductor.
>>In order not to leave gaps into which electromagnetic waves can intrude, the aluminium foil layer should be spread out as far as possible to create a 360 degree all-round contact with the shielding layer of the module.
>>When the conductive side of the shield is on the inner layer, the aluminium foil layer should be turned over to cover the outer sheath of the twisted pair and the twisted pair should be fixed to the metal bracket at the rear of the module using the nylon ties supplied with the shielding module. In this way, no gaps are left where electromagnetic waves can intrude, either between the shielding shell and the shielding layer or between the shielding layer and the jacket, when the shielding shell is covered.
>> Do not leave gaps in the shield.
2. U/FTP shielded twisted pair
The shield of a U/FTP shielded twisted pair cable also consists of an aluminium foil and a grounding conductor, but the difference is that the aluminium foil layer is divided into four sheets, which wrap around the four pairs and cut off the electromagnetic interference path between each pair. It therefore protects against external electromagnetic interference, but also against electromagnetic interference (crosstalk) between the pairs.
U/FTP pair shielded twisted pair cables are currently used mainly for Category 6 and Super Category 6 shielded twisted pair cables.
The following issues should be taken into account during construction.
>> the aluminium foil layer should be terminated to the shield of the shielding module together with the earth conductor.
>> the shield layer should form a 360 degree contact with the shield layer of the module in all directions.
>>to prevent stress on the core and shield in the shielded twisted pair, the twisted pair should be secured to the metal bracket at the rear of the module with the nylon ties supplied with the shielded module in the sheathing area of the twisted pair.
>> Do not leave gaps in the shield.
3. SF/UTP shielded twisted pair
The SF/UTP shielded twisted pair has a total shield of aluminium foil + braid, which does not require an earth conductor as a lead wire: the braid is very tough and does not break easily, so it acts as a lead wire for the aluminium foil layer itself, in case the foil layer breaks, the braid will serve to keep the aluminium foil layer connected.
The SF/UTP twisted pair has no individual shield on the 4 twisted pairs. It is therefore a shielded twisted pair with only a header shield.
The SF/UTP twisted pair is mainly used in Category 5, Super Category 5 and Category 6 shielded twisted pairs.
The SF/UTP shielded twisted pair has the following engineering features.
>> The twisted pair outer diameter is larger than that of F/UTP shielded twisted pair of the same grade.
>>not both sides of the foil are conductive, usually only one side is conductive (i.e. the side in contact with the braid)
>>the copper wire is easily detached from the braid, causing a short circuit in the signal line
>>The aluminium foil layer is easily torn when there is a gap.
Therefore, the following issues should be taken into account during construction.
>> the braid layer is to be terminated to the shielding layer of the shielding module
>>the aluminium foil layer can be cut off and does not participate in the termination
>>to prevent the braided copper wire from escaping to form a short circuit in the core, special care should be taken during termination to observe and check that no copper wire is allowed to have a chance towards the termination point of the module
>> Turn the braid over to cover the outer sheath of the twisted pair and secure the twisted pair to the metal bracket at the rear of the module using the nylon ties supplied with the shielded module. This leaves no gaps where electromagnetic waves can intrude, either between the shield and the shield or between the shield and the jacket, when the shield is covered.
>> Do not leave gaps in the shield.
4. S/FTP shielded twisted pair cable
S/FTP shielded twisted-pair cable belongs to double shielded twisted-pair cable, which is a cable product applied to Category 7, Super Category 7 and Category 8 shielded twisted-pair cable.
S/FTP shielded twisted pair cable has the following engineering features.
>> The twisted pair outer diameter is larger than that of F/UTP shielded twisted pair of the same grade.
>>not both sides of the foil are conductive, usually only one side is conductive (i.e. the side in contact with the braid)
>> copper wire can easily break away from the braid and cause a short circuit in the signal line
>>The aluminium foil layer is easily torn when there is a gap.
Therefore, the following issues should be taken into account during construction.
>> the braid layer is to be terminated to the shielding layer of the shielding module
>>the aluminium foil layer can be cut off and does not participate in the termination
>>to prevent copper wires in the braid from escaping to form a short circuit in the core, special care should be taken when terminating to observe and not allow any copper wires to have a chance to be directed towards the termination point of the module
>> Turn the braid over to cover the outer sheath of the twisted pair and secure the twisted pair to the metal bracket at the rear of the module using the nylon ties supplied with the shielded module. This leaves no gaps where electromagnetic waves can intrude, either between the shield and the shield or between the shield and the jacket, when the shield is covered.
>> Do not leave gaps in the shield.
Post time: Aug-10-2022