Sekundaarkääris

Sekundaarkääris, meaning "secondary coil" in Finnish, refers to the coil of wire in a transformer that receives its electrical energy from the primary coil through electromagnetic induction. In a typical transformer, the primary coil is connected to an alternating current (AC) source. This AC current creates a fluctuating magnetic field within the core of the transformer.

The secondary coil is also wound around the same core, or a core that efficiently couples the magnetic field. As the magnetic field from the primary coil changes, it passes through the secondary coil. This changing magnetic flux induces an electromotive force (EMF), or voltage, across the ends of the secondary coil. The magnitude of this induced voltage is determined by the ratio of the number of turns in the secondary coil to the number of turns in the primary coil, and the voltage applied to the primary coil.

Transformers are crucial components in electrical power systems for stepping voltage up or down. A step-up transformer has more turns in the secondary coil than in the primary coil, increasing the voltage, while a step-down transformer has fewer turns in the secondary coil, decreasing the voltage. The secondary coil's function is therefore central to the transformer's ability to efficiently transfer electrical energy and modify voltage levels for various applications, from power distribution to consumer electronics.