Home Technical Resources Technical Articles 2020/02/19 Technical Articles 3. Transformer Loading Transformers can provide a voltage on their secondary winding but to transfer electrical power between their input and output they need to be loaded. 2020/02/19 Technical Articles 2. Transformer Construction A simple two-winding transformer construction consists of each winding being wound on a separate soft iron limb or core which provides the necessary magnetic circuit. 2020/02/19 Technical Articles 1. Transformer Basics Transformers are electrical devices consisting of two or more coils of wire used to transfer electrical energy by means of a changing magnetic field.