Installation of current transformers

Current Transformer polarity

YOU MUST ALWAYS determine the directional flow of energy in the circuit before installation a current transformer

P1: Relates to the side on which energy flows from the source 

P2: Relates to the side on which energy flows to the load

Terminal Markings 

K: Relates to the side on which energy flows from the source (P1 = K)

L: P2: Relates to the side on which energy flows to the load (P2 = L)