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Ian Field Ian Field is offline
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Default Automotive relay question



"DaveC" wrote in message
...
I have a 12V SPST cube relay in my junque box. The diagram molded into the
relayıs housing includes a component connected in parallel with the coil
which looks suspiciously like a resistor.

Itıs not a back-emf diode: I connected the relay coil using both
polarities
(using a current-limited power supply) and the same current draw is
measured.


What is the purpose of this resistor?


There are such things as bidirectional transient suppressor diodes.

Although I've never seen it on a car relay - a resistor isn't impossible, it
could act as a "Q-spoiler" to damp inductive ringing.

Or a bit more likely - a VDR.