Assertion: modern lamp | /r/CapableOf | incorporate zener diodes
Facets:
value: often
type: TEMPORAL
value: to prevent overvoltage
type: PURPOSE
Source sentences:
text: Historically this was a nuisance, but modern lamps and dynamos often incorporate Zener diodes to prevent overvoltage, and dynamos can be designed to saturate beyond a certain voltage to protect the lamp.