FA 6 : Forced-Air, a cooling classification for transformers now classified as ONAF. Oil type, Forced circulation through cooling (i.e. cooling pumps) and natural convection flow in windings
Young & Company Electric Power Products and Related Engineering Services, Glossary of Electrical Terms, http://www.youngco.com/young2.asp?ID=4&Type=3, CA., USA 2001. (Electr Sfty - Amer) {514}