How is coil polarity determined?

Coil polarity is determined by the direction of rotation of the coil windings. In a typical coil, the way the wire is wound around the core establishes which side is the north pole and which side is the south pole. The right-hand rule can often be applied here: if you curl the fingers of your right hand in the direction of the coil winding, your thumb points in the direction of the magnetic field generated.

Understanding this concept is critical, as coil polarity affects how the coil interacts with magnetic fields in both motors and transformers. If the windings are reversed, the magnetic polarity will also be reversed, which can significantly affect the performance and operation of the electrical system.

The other factors mentioned do not determine coil polarity in the same way. The turn ratio relates to the number of turns in the primary versus the secondary coil, affecting voltage transformation rather than polarity. The direction of laminations pertains more to minimizing eddy currents in magnetic cores rather than establishing polarity. Saturation direction may refer to the point at which a magnetic core can no longer effectively contain a magnetic field, but this too does not establish the polarity of the windings themselves.