O le mataupu faavae o le tolu-vaega vavae transformer faavae faaaogaina le mataupu faavae o le electromagnetic induction. E saogalemu le faʻaaogaina o se transformer faʻaesea tolu-vaega, lea e masani ona faʻaaogaina e avea o se faʻaleleia o le eletise. O le vavae ese transformer e masani lava 1: 1 transformer, ae o loʻo i ai faʻamatalaga eseese. E tolu-vaega faʻaesea transformers e faʻaaogaina mo le suia o le voltage, moli, eletise ma le faʻasaʻoina o le eletise, faʻaaogaina lautele i pisinisi faʻapisinisi ma mining, eletise eletise, malaevaalele, fale maualuluga, alalaupapa ma isi nofoaga e manaʻomia le saogalemu o le afi.