A transformer has a secondary voltage of 24V and a VA rating of 480 with a turn ratio of 5:1. What is the voltage of the primary side of the transformer?

To find the primary voltage of a transformer, the turn ratio plays a critical role. The turn ratio can be expressed in terms of voltage as follows:

If the transformer has a turn ratio of 5:1, and the secondary voltage is known to be 24V, you can set up the relationship between the primary voltage (Vp) and the secondary voltage (Vs) as:

Vp / Vs = turn ratio.

In this case, substituting in the values gives:

Vp / 24V = 5.

To isolate the primary voltage, you multiply both sides by 24V:

Vp = 5 * 24V = 120V.

Therefore, the primary voltage of the transformer is indeed 120V. The voltage levels in transformers are directly related through their turn ratios, and using this relationship allows for the straightforward calculation of primary voltage given the secondary voltage and turn ratio.