Which two types of instrument transformers are commonly used?

The two types of instrument transformers that are commonly used are current and potential transformers. Current transformers (CTs) are designed to measure and transform high primary currents into a lower, manageable value that can be easily measured by standard instrumentation. This is crucial for electrical systems where direct measurement of high currents would be impractical or unsafe.

Potential transformers (PTs), also known as voltage transformers, serve a similar purpose for voltage. They step down high voltages to lower levels that can be safely measured and monitored by various electrical devices. By transforming the high voltage to a lower voltage, potential transformers enable accurate measurement and protection functions in an electrical system.

These two types of transformers are essential in power systems for metering and protection, ensuring that the electrical parameters can be monitored effectively without risking damage to measuring instruments or safety hazards.