Electrical Insulators
"An electrical Insulators is a material whose internal electric charges do not flow freely, and therefore make it nearly impossible to conduct an electric current under the influence of an electric field."
It is any material through which current does not flow. ex- wood, paper etc.
Materials are broadly classified as :
- Conductor
- Semiconductor
- Insulator
according to "electron band theory", there exists two bands: conduction band and valence band. between these bands exists an energy gap. in CONDUCTORS, the energy gap is extremely small, hence electrons jump from valence band to conduction band. in SEMICONDUCTORS, the The energy gap is narrower. The value of Eg =1.1eV for silicon crystal and Eg=0.7eV for germanium at ok. It can easily overcome due to thermal agitation or light. for INSULATORS, The conduction band of those material remains empty. The forbidden energy gap between the conduction band and the valence band is widest. The difference is more than 10ev. Crossing the forbidden energy gap from valence band to conduction band large amount of energy is needed.
Insulated in Copper Wire
Generally the electrical wires are covered with insulating materials, such as rubber-like polymers, varnish or plastic . Insulating and jacketing of wires and cables is done by passing them through an extruder nowadays. Initially , the materials used for insulation included various oil-based products and treated cloth or paper to learn more about electrical contractor.
The insulations of the electric cables are generally made up of plastic, but it is also classified into two types:
Thermo-stable insulation : these can be made up of EPR (ethylene-propylene) MICC (coated copper wire and insulated mineral or XLPE (cross-linked polyethylene),
Thermo-plastic insulation : these can be composed of PE (polyethylene), neoprene or plastic, PVC (polyvinylchloride) or PCP (polychloroprene),
How to clean insulated copper wire:
Stripping insulated copper wire before selling can increase its value. There are several ways to do this, and some of them are listed below.
1. Cutter for paper and cardboard .
If you have enough time, you can use a cutter to remove the insulation. Hook one end of the wire onto something solid. Now gently pull the wire and lower the blade along it close to the copper. Then pull out the copper. Heating the wire can make cutting easier. Be very careful not to cut yourself or injure others.
2. Heating the wire .
Heating is needed in order to melt the insulation. Do not breathe smoke or melt too much insulation at a time. It is dangerous to your health. It is likely that after firing, scrap of copper will cost less, or even nothing.
3. Wire stripper .
This is a reliable process, but it can take a long time. It is safer than a cutter.
4. Equipment for stripping wires .
It makes sense to buy if you are dealing with large volumes of copper wire. This is quite expensive equipment, and it is better that it does not stand idle.
5. The hammer.
In addition, you can hit the copper wire with a hammer until the insulation breaks. This is one of the worst ways to do this, as it is very time consuming and takes much more energy and time.
Insulating Material
Insulating Material is any material that inhibits the transmission of heat, noise or electric current.
Heat insulating material is often very light, having little mass and lots of volume, or a special resistance to the passage of heat either inwards or outwards (sensed as hot or cold). It can be anywhere from hard to soft, but it tends to be light and this is often from air bubble trapped inside the material.
Electrical insulating material is almost never metallic, but is always very resistant to the passage of current and voltage. Rubber and many plastics are used as electrical insulating material, for instance the outer layers of power cables. If metal is found in the insulating material it is there for armor and strength.
Sound insulating material is similar to heat insulating material but is mostly just a material that does not sustain vibrations and therefore does not transmit sound. It can transmit heat but some block both heat and sound well.
Shielding
Other forms of insulation are often called by other names, for instance insulation of magnetic flux is called shielding.
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