Mineral insulated cable (MI cable) is a specific form of cable that is utilised at high temperatures or hostile environments due to its low flammability, even when operating at higher temperatures. It is oxidation resistant and allows for precise measuring.
Copper wires are encased in a copper, stainless steel, or Inconel sheath, which is insulated with packed minerals such as magnesium oxide (MgO). Because it resists oxidation and ionising radiation, and it is chemically and physically stable at high temperatures, magnesium oxide is a great electrical insulation material. The MI cable can then be rolled under pressure to attain the appropriate diameter after being packed with MgO insulation.