Ensiökäämi

Ensiökäämi, also known as the primary coil, is a fundamental component in transformer construction. It is one of the two or more coils wound around a common magnetic core. The primary coil is connected to the input alternating current (AC) source. When an alternating voltage is applied to the primary coil, it creates a continuously changing magnetic field within the core. This changing magnetic field is the mechanism by which energy is transferred from the primary circuit to the secondary circuit.

The number of turns in the primary coil, along with the number of turns in the secondary coil and the magnetic properties of the core, determine the voltage transformation ratio of the transformer. In a step-up transformer, the primary coil has fewer turns than the secondary coil, resulting in an increased output voltage. Conversely, in a step-down transformer, the primary coil has more turns than the secondary coil, leading to a decreased output voltage. The design and material of the primary coil are crucial for efficient energy transfer and to prevent excessive heat generation due to resistance. Insulated copper wire is typically used for winding the primary coil.