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Author Topic: dont understand this relay, 120Vac / 12Vdc  (Read 277 times)
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West palm beach, FL
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i know its probably simple
but i went out and got this relay at radioShack and according to the writing on the relay i should be able to switch my mains ac
with at least 12v @30ma

i just do not know what goes connected to what  as far as where the one of the AC lines will be and where the microcontroller conection will be , and i do know that   i need to use a few other components so that i do not toast my microcontroller.

basically lets say if i want to control a regular lamp plugged into the wall ,
i would splice of the lines from the cord and connect on end to one contact on the relay and the other end of the splice the a different contact
thus when the coil is active the two spliced ends will be connected inside the relay

since i need 12v to turn the relay on, and another lower voltage to run my arduino ,
i will probably  just using that same line and step down the mains to 12v via transformer and bridge rectifier , maybe more then 12c since the diodes will drop it a bit , and use that for the relay

then a voltage divider or a goood old voltage regulator to power the arduino.

but right now i just would like some insight on how this relay gets hooked up

so sorry the images come out like that, they look right side up on my phone


I could print the Arduino logo on a box of cereal and sell it as "Arduin-O's"

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You could use a 12VDC wall wart to power the Arduino and the relay (diode across the coil).
Make sure the voltage regulator on the Arduino is not running hot.

The way you have it in your schematic isn't the same as how you have it wired up! That goes for me too.

Cumming, GA
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then a voltage divider or a goood old voltage regulator to power the arduino.

Never use a voltage divider as a power source for "active" electronics.

You want a transistor to drive the relay from the pin.

* driver.jpg (69.7 KB, 914x481 - viewed 23 times.)

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