taking anybody out of service, you can fix a magnetized
CT in less than one minute!"
Many of you have measured
ratio test reading of a CT that was not what it should
be: For Example, a 200:5 CT that measured out to be
212:5 but passed the burden test. This is a magnetized
CT. And what can you do about it? Either nothing or
change the CT. Now there is a 3rd option: The Spinlab
Demag Circuit used in tandem with the Bird Dog Plus.
Of the 32 failure modes of
a meter circuit, magnetized CTs are by far the most
common ones after installation errors. A magnetized CT
can be caused by a lighting strike, ground fault, or
open circuiting a CT.