Electrical insulator thermal conductor is two type used products. Any poor conductor of heat, sound, or electricity is an insulator. Most substances lacking free (mobile) electrons, such as non-metals, are electrical or thermal insulators. Plastics and rubber are good insulators.

How do conductors and insulators work together safely?
If you are talking about electrical conductors and insulators, we are using the insulators to cover the conductors so people and objects cannot touch the conductors. You can see this if you take a look at the power cord of any appliance: inside the plastic are metal wires. The conductor (the metal wires) can easily transport electrons while the plastic can't which means that electricity will not go through the plastic and will remain in the metal wires. Hence, people or objects that touch the power cord will not receive electrical shock. In the substation, we must install electrical insulator, such as porcelain pin type insulator.

About thermal conductor
Thermal energy is different from electrical energy.
Carbon is a good thermal conductor because it has a high heat of formation (enthalpy). On one hand, Carbon is a nonmetal so it does not conduct electricity.

Moreover, Carbon atoms in diamond are covalently bonded. Therefore, the electric current cannot travel spontaneously because electricity travels best in ionic bonding.

Electrical insulator thermal conductor has been into our lives. Such as distribution line is used with porcelain pin insulator, pin post insulator and shackle insulator.

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