Assertion: electric motor's field | /r/HasProperty | provided
Facets:
value: from permanent magnets
type: OTHER
value: by using permanent magnets
type: MANNER
Source sentences:
text: The magnetic field for a synchronous machine may be provided by using permanent magnets made of neodymium-boron-iron, samarium-cobalt, or ferrite on the rotor.
text: The field is supplied from a separate voltage source, usually with constant field current, or from permanent magnets.