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Shielded Cables
Chetan Shielded cable
ensures signal integrity and provides confidence in audio and video
transmissions, preventing downtime and maintaining sound and picture
clarity. Among the shield types available are braid shield, foil
shield, combination shields and lapp shields.
Braid Shield: Braid
shield consists of groups of tinned or bare or silver plated copper or
aluminium strands, one set woven in a clockwise direction and
interwoven with another set in a counter clockwise direction.
Braid shields provide
superior structural integrity, while maintaining good flexibility and
flex life. These shields are ideal for minimizing low frequency
interference and have lower DC resistance than foil. Braid shields are
effective at audio, as well as RF ranges. Generally, the higher the
braid coverage, the more effective the shield. However, the trade-off
between cost and braid coverage must be considered. Typical braid
coverage are between 80% and 95%. Coverage of 100% is unattainable with
a braid
shield.
Foil Shield: Foil
Shield consists of Aluminium Foil laminated to a polyester or
Polypropylene film. The Film gives the shield mechanical strength and
bonus insulation. Foil shield provides 100% cable coverage, necessary
for electrostatic shield protection. Because of their small size, foil
shields are commonly used to shield individual pairs of multipair data
cables to reduce crosstalk. Drain wires are used with foil shield to
make termination easier and to ground electrostatic discharges. The
shortcoming in using the foil shield include higher DC resistance and
lower mechanical strength than braid or spiral shield.
Lapp Spiral Shield: A
spiral shield consists of wire usually copper wrapped in a spiral
around the inner cable core. Superior flexibility and flex life, ease
of termination and upto 97% coverage are the advantage of spiral
shields. They are best suited for audio applications. As a rule spiral
shields are not suitable above the audio frequency range due to coil
effect produced by the inductance of the spiral wire strands.
Combination Shields: These
consisit of more than one layer of shielding. They provide maximum
shield efficiency across the frequency spectrum. The combination
foil/Braid shield combines the advantage of 100% foil coverage plus the
strength and low DC resistance of the braid.
Most of our shielded
cables are available ex-stock in a wide variety of colours and
packages. Many of these are available off the shelf from our
distributors. If you have a new or unusual requirement, you can contact
us.
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