Close spacing is the key to low inductance. Twisting two conductors together causes then to be in intimate contact over the length and therefore will result in lower inductance. Parallel wires, if in tight contact will also have low inductance. It is just easier to twist them to get the close spacing. ROMEX has a large spacing between the conductors and therefore has high-inductance. I have a table on my website that compares the inductance of ROMEX and various cords. See the Power Cable page at:
http://www.empiricalaudio.com
BTW, the best construction is to use solid 12 gauge THHN wire twisting the hot and neutral together and then twist the ground around them in the opposite direction. Put this inside a plastic conduit to meet code.
http://www.empiricalaudio.com
BTW, the best construction is to use solid 12 gauge THHN wire twisting the hot and neutral together and then twist the ground around them in the opposite direction. Put this inside a plastic conduit to meet code.