In a isolation transformer number of turns in primary side is equal to number of turns in secondary side. Which means the turn ratio or transformer ratio of isolation transformer is 1:1. Its main function is to isolate one circuits from another circuits.
An isolation transformer is made of two copper coils that are wound around each other and are each supplied by their own power source. While the term “isolation transformer” technically refers to any transformer, it is specifically a transformer that isolates a circuit from an alternating current. An isolation transformer does this by separating two circuits with an induction loop or decreasing the alternating current’s voltage before it reaches the circuit itself.