Mean Length Turn, sometimes Mean Length per Turn is the mean length of winding turn in a coil. Usually an acronym MLT is used. The dimensions of a coil former or bobbin define the MLT of a full wound coil. In some cases the coil is not made of a single wire with multiple turns, and a coil former is not always necessary, but may be constructed in a stack of printed circuit layers. The MLT is an important measure in the design of inductors, transformers and other wound electromagnetic components.
References
Mean Length Turn Wikipedia(Text) CC BY-SA