MC stands for Metal Clad which is this electrical cable’s part number because of the aluminum interlocked armor covering the THHN THWN copper conductors. The aluminum armor wraps around the conductors staying connected to itself with the ability to easily unwrap for wire stripping during installation.
MC cable 8-2 actually has 3 total wires in it when including the green insulated ground wire. The ground wire is 10 AWG stranded instead of 8 AWG because the grounding wire doesn’t need to be as powerful as the main conductors. When the cable is as large as 8 AWG the copper only comes in stranded rather than solid because a solid 8 AWG piece of copper is very inflexible.
Electricians, installers and contractors like to have stiff wires instead of flexible because of pushing it through conduit and installing it in walls of homes and buildings. However, a solid strand of 8 AWG is a bit much because it will barely bend around corners or snake through the curves of conduit.
Metal Clad 8 AWG 2 Conductor with ground weighs about 231 pounds per 1000 feet and has an outer diameter of.644 inches. It’s rated for 40 AMPS in 60ºC, 50 AMPS in 75ºC and 55 AMPS in 90ºC so you’ll need to know the temperature it will reach in the application before choosing the correct size electrical cable for the job. MC 8-2 comes in standard 200 foot coils and 500 foot reels however most suppliers will cut any length you need for your installation.
The pricing on all copper MC cable will be done on a day to day basis due to copper increases and decreases on the NYSE. As the copper price increases suppliers will also increase their pricing to match current price points. Unfortunately, you probably won’t see prices go down as quick when the price of copper drops because suppliers already have inventory at a particular cost and won’t want to lose money if they can help it. Either way, buying your copper electrical wire while the price of copper on the NYSE is going down will prove to save you money over the course of the year.
Speak to your supplier about MC cable to determine if it’s the correct wire for your installation. An electrician can also help you understand which approvals and gauge size you’ll need to meet the NEC code for the each type of installation.