The standard current transformer, functioning as a calibration device, is used to verify the accuracy of current transformers with two or fewer levels of precision below it.
A current transformer consists of a primary winding and a secondary winding, as illustrated in Figure 1. During wiring, strictly follow the current ratio specified on the terminal block. L1 and K1 are the polarity terminals for the primary and secondary windings, respectively. When core penetration is required, La serves as the polarity terminal.