The CBEMA (Computer and Business Equipment Manufacturers' Association, typically
pronounced sa-BEEM-ah) power quality graph plots the depth of voltage sags on the vertical
axis against the duration of voltage sags on the horizontal axis.
The green line on the graph shows the sag immunity suggested by CBEMA.
The sags above, shown as blue dots, were collected at world-wide semiconductor plants
For more information, see SEMATECH TT#99063760B-TR. Clearly, many of these sags were
deeper and longer than the CBEMA recommendation.
This observation led the semiconductor industry to establish its own voltage immunity standard, SEMI F47.
CBEMA has developed into ITIC; check the Tutorials & Info page for more information.
Power Standards Testing Labs specializes in testing to this SEMI standard, and offers sag generators to people who want to do their own testing.