Alternating Current 07 : (AC) An electric current that reverses its polarity at rapid regular intervals. In North America, the current contains 60 complete cycles per second and Europe, 50 cycles per second
Ralph W. Burklin & Robert G. Purington, Fire Terms: A Guide to Their Meaning and Use, National Protection Association, Boston, MA 1980 USA. (Guide: Meaning and Use, Nat Prot Association Fr Srvc - Amer) {457}