Potential power or voltage transformers change commercial power from generators to high voltage and low current for nationwide distribution. Substations use similar transformers in reverse to reduce the voltage and increase the current to usable levels. In the home and in industry, potential transformers have thousands of other uses. TVs and cell phone chargers have potential transformers to raise or lower the voltage for internal distribution and use.
Transformers designated as current transformers have far more limited uses. Current or current sense transformers only lower current for use in meters and measuring devices, with little regard for power or voltage changes.