Any transformer, single or three phase in which primary and secondary are separately wound (double wound) is an isolation transformers as primary and secondary are internally isolated from each other. The power transfer, at rated frequency, is by transformer action through mutualmore...
Any Double Wound Transformer is internally an isolation transformer as the primary and secondary are isolated from one another through insulation. However, modern machines and systems need a truly isolated, clean and stable power requirement. This is ensured by an Ultra Isolationmore...