undervoltage
Noun
Meaning
undervoltage (countable and uncountable, plural undervoltages)
A voltage that is too low.
Synonyms
Examples
The battery can still be charged while "bucking" an overvoltage, but while "boosting" an undervoltage, the transformer output is too low to charge the batteries.
This type of UPS is able to tolerate continuous undervoltage brownouts and overvoltage surges without consuming the limited reserve battery power.