3 pin relays seem useless, am I right ?

Since the input +ve voltage will be shared by controller * circuit & output pin, then input has enough ampere to satisfy the load. Then why not just c
onnect input directly to the load ? This will save the ampere used by the * i.e. less heat ( esp for hot climate ) & more amps for e.g. spark plugs / starter motor, less cost & weight too.
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On 4/02/2016 11:27 PM, snipped-for-privacy@gmail.com wrote:

Show us a circuit so we might get a glimmer of what you are on about !!
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Google usenet does not let me post any diagram. Now in Msia, no ISP has a nntp server. Youtube has a video ( listed by Yahoo, when I searched for 3 pin relay )with diagrams of 5, 4 & 3 pin relays.
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On 5/02/2016 2:30 PM, snipped-for-privacy@gmail.com wrote:

There''s Dropbox for one. What do you mean by "3 pin"??
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On 04/02/16 15:27, snipped-for-privacy@gmail.com wrote:

The wiring for any controlling switch, and the switch itself, will have to be rated for the load current if you don't use a relay. More copper, size and safety risk for these parts.
--
Adrian C

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On Fri, 5 Feb 2016 11:23:06 +0000, Adrian Caspersz

If you think of the relay like a transistor in "emitter follower" it makes perfect sense.
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