All-or-Nothing Relay : An electrical relay which is intended to be energized by a quantity, whose value is either higher than that at which it picks up or lower than that at which it drops out
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}