Glossary of Terms blackout. Total loss of utility power caused by excessive demand on the power grid, lightning storms, ice on power lines, car accidents, backhoes, earthquakes and other catastrophes. VA times 1000. Electrical noise is caused by many factors and phenomena, including lightning, load switching, generators, radio transmitters and industrial equipment. It may be intermittent or chronic.
Noise introduces glitches and errors into executable programs and data files.
Also known as brownouts, sags are short term decreases in voltage levels. Electric companies use sags to cope with extraordinary power demands. Hot summer days, when air conditioning requirements are at their peak, will often prompt rolling brownouts. Sags also reduce the efficiency and life span of electrical equipment, particularly motors. Also referred to as an impulse, a spike is an instantaneous, dramatic increase in voltage.