Shielded Cable

What is shielded cable used for?

shielded cable is use for transferring data in the form of electronic signal.

Why we use shielded Cable?

When we are transferring data from source to destination then there is chance of distortion of data due to EM wave. To protect our data from distortion we use an extra layer of conductive material in the form of foil, braid, sprial etc. This extra conductive material layer is wrapped with our data cable and provide it protection from EM waves and EM Noise.

Is coaxial cable shielded?

yes, Coaxial Cable are also shielded but we know them by the name of "Coaxial Cable" and Coaxial Cables are mostly know as RG-6(used for cable TV in home),RG-11 and RG-59, where RG means "Radio Guide" .These cable are used for high frequency signal transmission.

RG-6 Armoured cable

Why we use CCS material in RG-6?

As high frequency signal travel through the Coaxial Cables therefore due to skin effect signal travel through outer surface of conductor that is way we can easily use Copper Clad Steel (CCS). As in this wire outer copper layer takes care of high frequency signal transmission & Steel takes care of the load.
CCS conductor is used for long distance transmission, as it offers high strength, economy & longer life. These cables withstand all mechanical abuses during operation and are extensively used in DTH and CATV(cable television)

Type of shielding in shielded cable

There are two different type shielding Foil Shielding and Braided Shielding.
Braided Shielding, Most commonly we can see this type of protection in the Coaxial cable, Which we are using as Television(TV) Cable. In Coaxial cable we are mostly using braided protection. But braided protection does not provide 100% coverage from EM Waves therefore foil protection is use for provide 100% coverage. For better protection from EM wave we use combination of foil and bread protection.
NOTE:-Shielded cable also known as screened cable, instrumentation cable, BMS cable. 

Type of shielded cable

1. Flexible shielded cable(Foil Shielded).
2. Armoured shielded cable(Foil Shielded+Armoured).
3. Shielded Cable with tinned copper braiding(Braided Shielded).
4. Shielded cable with Aluminium Mylar tape and Drain wire(Foiled Shielded Cable)
5. Shielded cable with Aluminium Mylar tape, Drain wire and additional braided Shielding by tinned copper which provide 100% coverage.(Foil+Braided Shielded)

Shielded cable easily available in 2 core to 24 Core, 1 Pair to 12 Pair,1 Triad to 12 Triad and size 0.5mm to 2.5mm. 

As cable come in pair and tride therefore there are two type of shielding overall Shielded and Individual +overall shielded.

NOTE:-BMS cable are in multi-colour upto 4 Core and after that they mostly available in grey with numbering. 

Cost of shielded cable.

The cost of shielded cable is changing company to company, number of core ,armoured and unarmoured. The cost of 1mmX4core Flexible shielded cable is around 50 rupees per meter, But the cost of 1mmX4core armoured is around 80 rupees per meter.
Note:-whenever the number of process increase to make a cable its cost automatically increase therefore cost of shielded cable is more than normal cable

Twisting Difference between BMS and Instrumentation cable

Pair:- Two cores twisted to form a pair.

Triad:-Three cores twisted to form a Triad.

Quad:-Four cores twisted to form a Quad.