Equipment - Variable TransformersA variable transformer, also known as a variac, is a type of test and measurement equipment that is used to control the voltage of an electrical circuit. It is a transformer with a continuously adjustable output, which allows the user to adjust the voltage in the circuit over a range of values. Variable transformers are commonly used in applications where the voltage needs to be adjusted or varied, such as in testing, experimentation, or production. They are available in a range of sizes and ratings, and can be used with both AC and DC circuits. Variable transformers are often used in conjunction with other test and measurement equipment, such as multimeters, oscilloscopes, and power supplies, to provide a complete test and measurement system.