What is a DC Immune current sense transformer?

DC immune current sense transformers are used for sensing the AC currents where DC offsets also exist. The current sense transformers create a voltage when current flows. They are primarily made for sensing AC currents in a circuit so having a DC bias can distort the AC measurement.

Some specialized alloys of magnetic materials are referenced as DC immune. For example the CR8300 series. DC immune means that they will not react or distort the AC measurement so there can be more accurate AC measurements even if there is a DC offset present.