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Construction of Instrumentation Cables

With the spread of signal-based instruments around us, the role that instrumentation cables play around us has also increased. In fact, the working of many of our essential instruments depends on the reliability and functioning of these cables. So, let us take a good look at these. Instrumentation cables are used mainly to send low energy signals that are used in the operation of many instruments. Instrumentation cables manufacturers’ biggest market lies in data transfer, voice transmission and for controlling circuits. Some of the common uses for instrumentation cables are in:

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Broadcasting OGP industries Industrial equipment control Assemble equipment Mass transit systems Communication services Instrumentation Cables Instrumentation cables may look like any other thick cable, but it is far from your basic cables. Its ability to transmit signals is far superior to others. There are two important properties that make to ideal for data transfer and communication systems.

It allows for an authentic transferring of signal. Sound transferred will be purer and almost its authentic version.

It cuts down on almost all interruptions. This means an uninterrupted signal transference. So sound transmitted will be unbroken and smooth. There will be no distortions. Construction In a typical construction instrumentation cables manufacturers will use a conductor around which is the dielectric insulator. There could be a metal shield and this is enveloped in a plastic (usually PVC) jacket. Conductor: Instrumentation cables may carry a single conducting wire or a combination of wires. In case of multiple conductors, the wires are not insulated against each other. Other than the number of

conductors, the material and size are also major considerations. Both single and multiple cable has its own use. Instrumentation cables usually have a pure EC grade copper conductor. A good quality cable conductor will have excellent conductivity and flexibility. Copper is preferred because of features excellent resistance to corrosion that is coupled with its high thermal conductivity. It is also relatively light with low strength-to-weight ratio. This makes the cables lighter without diluting its effectiveness. Aluminium and steel are also used sometimes. Steel conductors usually have a copper or aluminium shell. The size of the conductor is very important because it can decide the flexibility as well as current carrying capacity. The smaller the diameter of the conductor, the thinner it is. Thinner wires have higher resistance and will hence, carry less current and vice versa. Shielding: The multiple sheathing often found in these cables are meant to provide an almost foolproof barrier. The shielding material is electromagnetic. It occupies the space that lies between the outer jacket and the conductor. It is usually construction of metal tape, metal braiding, or foil braiding. Some cables may also have a drain wire or a grounding wire in the shield. The purpose of the shield is to prevent any electrical noise from interrupting the signal being carried, while reducing the emission of electromagnetic radiation from inside the cable. In other words, it protects the signal carried inside while barring any interruptions from outside. The barriers also give it high protection in adverse conditions. Jacket: Like the shielding, the jacket is also very important in reducing leaks and protecting the structure underneath.

Instrumentation cables manufacturers today use a wide range of materials to make the jacket. The material is also an important factor when selecting a cable. Some of the commonly used materials are: 

Ethylene Propylene Diene Elastomer or EPDM: It has high flexibility and high resistance to a wide temperature range.

Neoprene: This synthetic rubber is found commonly when we are dealing with chemicals because of its resistance to chemicals, oils and fire.

Silicon rubber: It is preferred for its superior flexibility. However, it lacks resistance to liquid and is relatively less strong.

Thermoplastic: Common variants are PE, PVC and Teflon. Different thermoplastics may have different properties, but all of them form perfect insulating material because of their high flexibility and corrosion resistance. PVC is perhaps the most commonly found instrumentation cable insulating material.

Mica tape: It is used in some specific applications because of its ability to withstand high temperature resistance. Instrumentation cables manufacturers also have to adhere to some very strict standards laid down for cable manufacturing. There are many types of instrumentation cables, characterized by their construction and usage. Understand the basic construction before looking at the various types.

Source : Construction of Instrumentation Cables

Construction of instrumentation cables  
Construction of instrumentation cables  

With the spread of signal-based instruments around us, the role that instrumentation cables play around us has also increased. In fact, the...