Word forms: (regular plural) contact breakers
noun (Automotive engineering: Vehicle components, Lighting and electrical/electronic systems) A contact breaker is a mechanical switch, activated by a rotating cam, that makes or breaks the ignition circuit to send a spark to the spark plug. ⇒ The contact breaker is a mechanical device in the distributor system and is used to break the circuit. ⇒ When the primary circuit is broken the current tends to continue flowing and a spark jumps across the separated contact breaker points. ⇒ The contact breaker is a mechanical device for breaking and making the primary circuit.
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