Shorted Turns Detection
Introduction to Shorted Turns
Inductors are made up of a length of wire, usually
around a core.
The core is usually some type of magnetic material
iron or ferrite, however air cores are also sometimes used.
The wire, is referred to as
“winding”, and this winding is made up of a number of turns.
Generally, inductors are a
winding, and transformers mostly have multiple windings, (there are
cases, such as “Auto transformers” where only a single winding
in many transformers different wire diameters can be used in the
are wound using a large number of turns and/or using very fine wire,
method of detecting the existence of shorted turns, and also the
stress the winding in order to detect imperfections or potential
the winding insulation that could be a weak point over time.
Winding imperfections can
be attributed to damaged enamel caused by physical damage during
the transformer, or imperfections during the manufacture of the raw
These imperfections can
shorted turns during normal operation if undetected at point of
The high temperatures
from the increased current at the short will fairly quickly cause
melting and create a low resistance spot weld.
This low resistance short
completely short out one turn, affecting the performance of the
winding and hence
the whole transformer