This circuit diagram shows a ferrite core current transformer (CT) with a 450 turn winding connected to measure the current from a 120V, 1 phase 60Hz AC line powering a 50Ω load. The variac is used to adjust the voltage to the load and the CT is required to measure a minimum current of 1.54A through the load.

1. 50 Ω
load
450 turn
ferrite
core CT
IP(1.54 A minimum)
Load
120 V
1 phase 60
Hz AC line
Variac