Editing Relay (section)

=== Contactor ===

A [[contactor]] is a heavy-duty relay with higher current ratings,<ref>{{cite book |editor1-first=Terrell |editor1-last=Croft |editor2-first=Wilford |editor2-last=Summers |title=American Electricians' Handbook |edition=Eleventh |publisher=McGraw Hill |location=New York |date=1987 |isbn=978-0-07-013932-9 |page=7{{hyphen}}124<!--HYPHEN PAGE--> }}</ref> used for switching [[electric motor]]s and lighting loads. Continuous current ratings for common contactors range from 10 amps to several hundred amps. High-current contacts are made with alloys containing [[silver]]. The unavoidable arcing causes the contacts to oxidize; however, [[silver oxide]] is still a good conductor.<ref>{{cite book |title=Electrical control for machines |first1=Kenneth B. |last1=Rexford |first2=Peter R. |last2=Giuliani |edition=6th |publisher=Cengage Learning |year=2002 |isbn=978-0-7668-6198-5 |page=58 |url=https://books.google.com/books?id=5RkbwbYq1joC&pg=PA58}}</ref> Contactors with overload protection devices are often used to start motors.<ref>{{cite web|title=Contactor or Motor Starter – What is the Difference?|url=http://eecoonline.com/contactor-or-motor-starter/|website=EECOOnline.com|access-date=2018-04-19|date=2015-01-13}}</ref>