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I'm very new with working with electronics like this and need some advice.  

I'm trying to build and RFID door lock(yeah i know..very original) that triggers a 12V electric strike lock.  How  do i provide this power?  As much description as possible would rule.  I'm a noob with the hardware/physical side of this.
« Last Edit: November 08, 2011, 11:36:01 pm by kylec123 » Logged

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http://www.dipmicro.com/store/DCA-1210

How much current do you need?

You can use arduino to read the RFID, turn on a relay and let the 12V be applied across the strike lock, which I imagine is similar to a solenoid.
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"and let the 12V be applied across the strike lock,"

I think this is what i do not know how to do.   
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You're going to have some electromechanical thing that moves out of the way to unlock the door, yes?
Pick a mechanism for that, mount it, and bring out two wires from to connect up to a relay so that current can be run thru it similar to a motor.
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Ok, so i need a relay.

This is what im using
http://www.ebay.com/itm/Electric-Strike-Door-Lock-Fail-Secure-NO-Long-plate-/160446497488?pt=LH_DefaultDomain_0&hash=item255b5b42d0#ht_2629wt_754

What relay would you suggest getting?  Obviously a 12V one but i've never messed with one before.  Any help?
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Something like this
http://www.mpja.com/prodinfo.asp?number=18474+RL
5V coil, resistance >=125 ohm so current is 40mA or less (5V/125 ohm = 40 mA)
Contacts that handle 12V & 450mA
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Unless you need to isolate the 12v supply from the Arduino supply, I'd use a transistor rather than a relay - it will cost less, consume less power and be more reliable (as long as you remember to include a diode across the coil of the lock).
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