Jan. 10, 2019
Mineral Insulated Metal Sheathed Cable is also a ultra-reliable, exceptionally robust wire. It's acceptable for the toughest applications which have instrumentation and electricity in hazardous places, outside use such as services, feeders and branch circuits, atomic reactors, and exceptionally high ambient temperatures. Maximum circuit rating, based upon the producer, is just 1 kV.
This Mineral Insulated Cable consists of one or more (up to 19) copper conductors inside a continuous copper sheath, which provides excellent corrosion and mechanical protection. It also serves as an equipment-grounding conductor. (A stainless-steel sheathed variant requires an additional copper equipment-grounding conductor.)
The Aluminum Conductors within the aluminum sheath are insulated and separated from one another with a sterile calcium oxide powder that's released during the production procedure.
MI Cable is permitted in all locations except where the copper sheath can be damaged either mechanically or by corrosion. Specifically, in underground runs, the cable must be protected from physical damage. And there’s a need for additional protection when the cable sees conditions that are destructive or corrosive to the copper sheath.