Magnetic wrap up effects screening

A system for screening a current transformer for magnetic wrap-up effects, the system comprising:

• a nest having at least one terminal, the nest configured for coupling to the current transformer via the terminal and receiving an output signal from the current transformer during screening;
• a rotatable external conductor formed into a loop, the loop configured to be positioned in proximity to the current transformer, wherein current in the loop generates a magnetic field when the external conductor is energized;
• and
• a test module coupled to the nest, the test module configured for comparing the output signal of the current transformer when the external conductor is not energized to the output signal of the current transformer when the external conductor is energized, the test module configured to screen the current transformer for a susceptibility to magnetic wrap-up effects based on the comparison.

A method of screening a device under test, the method comprising:

• positioning a rotatable external conductor in proximity to the device under test, the external conductor formed into a loop;
• obtaining an initial output signal from the device under test;
• energizing the external conductor, wherein current in the loop generates a magnetic field in proximity to the device under test;
• rotating the external conductor relative to the device under test through a plurality of radial positions;
• obtaining one or more subsequent output signals from the device under test at the plurality of radial positions;
• comparing the initial output signal of the device under test when the external conductor is not energized to the one or more subsequent output signals of the device under test when the external conductor is energized;
• and
• determining a susceptibility of the device under test to magnetic wrap-up effects based on the comparison.