interrupter vs telephone exchange

interrupter

noun
  • A device for opening and closing an electrical circuit. 

  • One who or that which interrupts. 

  • An interpreter (person who interprets speech in a foreign language). 

telephone exchange

noun
  • any equipment that establishes connections between telephones 

  • the rooms housing such equipment 

How often have the words interrupter and telephone exchange occurred in a corpus of books? (source: Google Ngram Viewer )