What is a shielded cable?
The prosecution cable is an electrical cable in which the conductor and its surrounding insulation layer were closed in one or more conductive shields. These are usually made of metal foil or knitted wire. A protective jacket usually forms an outer layer. It works to minimize electromagnetic interference (EMI) emimized by the emitted and received by the cable.
Power cables can be the main source of EMI in the environment. These may act as antennas for interference transmission or as receivers in obtaining and performing interference for other devices. The EMI level is the result of the requirements for powering any electrical equipment in operation. The factory floor would usually have the surrounding EMI level higher than the office or residence. The degree of shielding necessary to alleviate the interference will vary accordingly. The effect is commonly referred to as noise. The coaxial cable is a familiar version of the shielded cable, often used in the transmission of radio frequencies, distribution of cable TV and computer network. Safety systems in the areaECH, subject to increased EMI, use shielded cables to help prevent false alarms.
Prosecution can alleviate EMI in two ways. May reflect interference or can interfere with the ground. EMI is either negated or thus reduced by power that it has no noticeable effect on the conductor.
Theshielding degree in the cable depends on several factors that primarily include the surrounding EMI in the environment. The cost and necessary diameter, as well as the weight and flexibility of the cable, are all other factors. The unwavering cable can be acceptable for use in an industrial environment if its immediate environment can be strictly controlled.
Two types of shielding are most commonly metal foils Affilled wire. The shield foil uses a thin layer of aluminum or copper supported by a polyester insert for strength. This technique provides excellent wire coverage, although the film is somewhat fragile. Connecting connector and grounding canbe difficult. The drain wire that is an uninsulated conductor is sometimes used to end and ground the foil.
Knitted shield is a mesh woven from copper wire. This does not provide as effective coverage as foil. Copper conductivity and most of the wire network cooperate to make COP an effective choice. It is also much easier to connect the connector and end to the ground. This type of cable is more expensive than foil and increases the likelihood of size, weight and flexibility.
In the areas of extremely high EMI, double shield access was used. The protected cable has an inner foil shield and an outer layer of knitted copper. This approach uses greater foil coverage and superior copper braid conductivity.