UNDERFREQUENCY RELAY
Meaning of UNDERFREQUENCY RELAY in English
ˈ ̷ ̷ ̷ ̷ˌ ̷ ̷ ̷ ̷ ̷ ̷- noun
Etymology: under (III) + frequency
: a relay actuated by a fall in electrical frequency
Webster's New International English Dictionary.
Новый международный словарь английского языка Webster.
2012