A voltage transformer, often called an instrument or potential transformer, is designed to reproduce system voltage at a lower, safe level for metering and protection devices with high accuracy and low burden. A power transformer is built to transfer significant power between circuits, prioritizing efficiency and thermal performance rather than precise ratio accuracy. Voltage transformers operate at low VA ratings and are part of measurement circuits, while power transformers handle kVA or MVA, feeding loads or other network sections. Their insulation, construction and testing requirements differ accordingly.