IEEE C62.11a:2008

Amendment Standard - Superseded.
Metal-oxide surge arresters designed to repeatedly limit the voltage surges on 48 Hz to
62 Hz power circuits (>1000 V) by passing surge discharge current and automatically limiting the
flow of system power current applies to this amendment. This amendment covers devices for
separate mounting and to those supplied integrally with other equipment. The tests demonstrate
that an arrester can survive the rigors of reasonable environmental conditions and system
phenomena, while, at the same time, protect equipment and/or the system from damaging
overvoltages caused by lightning, switching, or other undesirable surges.

This standard applies to metal-oxide surge arresters (MOSAs) designed to repeatedly limit the voltage surges on 48 Hz to 62 Hz power circuits (>1000 V) by passing surge discharge current and automatically limiting the flow of system power current. This standard applies to devices for separate mounting and to devices supplied integrally with other equipment.
NOTE—These tests demonstrate that an arrester can survive the rigors of reasonable environmental conditions and system phenomena while protecting equipment and/or the system from damaging overvoltages caused by lightning, switching, and other undesirable surges.