FAQ:Is it necessary to Twist the Power Bus Wires?

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Yes, and no. Mostly yes.

The reason for twisting the bus wires is to reduce the inductance of the wires, which results in a lower impedance.

To accomplish this, it isn't necessary to twist the wires together, just tying them together with cable ties accomplishes much the same results.

All wires have inductance. This property is a function of the length and diameter of the conductor.

  1. As the length increases, so does the inductance.
  2. As the diameter decreases (smaller gauge number) the inductance increases.

Believe it or not, by keeping the bus wires together, their mutual inductance actually reduces the total inductance of the bus. As the impedance of the bus equals the square root of the sum of the squares, a small change in the reactive inductance results in a much larger change in the impedance.