Thread: 5v relay wiring help!

NC NO

L1 L2 COM



Connect 5V and gnd to L1-L2. That will energize the relay coil. Connect 12V to NO and it will be switched to COM when the relay is energized.

ok i kinda thought that was how it went but the relay makes a buzzing sound, i got it from radioshack it looked like it was opened before so i guese its bad. Thanks for your help

Is that pinout looking from the topside of the relay or from the bottom (where the pins are)? You can find out if the relay matches the pinout with an ohmmeter. Resistance between the coil L1-L2 leads should be low but not zero, maybe a few hundred ohms. The COM-NC will read shorted, near zero. The NO lead should not give any reading with respect to any other lead unless the coil is energized.

You can make any relay operate as a buzzer: connect V+ to NC, COM to L1 or L2, and ground the other coil lead. The relay will turn on, breaking the connection and allowing it to turn back off. Then when the armature comes to rest on the NC contact it will turn on again, repeating the process.

If you operate a 5V relay off 12V, it will still actuate. It will draw more current than intended and probably overheat. I say all of this becaus there is a good chance your relay isn't bad. It might be you have the wrong pinout, or the wrong part was in the package when you bought it.

the pinout is looking from the bottom and is correct since there is only 5 pins. the coil reads 0.06 on 20k ohm. I got 5v+ signal going to L1, 12- going to L2, and 12+ to COM, but still no power switched to NO. I checked the power output on my signal and it is not 5v its like 3.54 and think this is the problem. I think I might have to get another relay that can trigger off of 3.54.

would this work? Thanks
http://cgi.ebay.com/FOTEK-SOLID-STAT...QQcmdZViewItem

Originally Posted by aalouie

would this work? Thanks
http://cgi.ebay.com/FOTEK-SOLID-STAT...QQcmdZViewItem

That is much bigger and more expensive than a relay. It should work though.

Edit: I just looked again and the SSR is for AC loads. It won't work for DC. You can get one that is for dc though.

Originally Posted by JimmyFitz

That is much bigger and more expensive than a relay. It should work though.

No. It won't work for the application in question. Not to mention the 1.6V voltage drop due to the internal diodes.

Originally Posted by eastvolt

No. It won't work for the application in question. Not to mention the 1.6V voltage drop due to the internal diodes.

What is the application? I don't recall that the OP ever said. I see that the relay is for switching AC loads. So I stand corrected, it won't work.

Originally Posted by JimmyFitz

What is the application? I don't recall that the OP ever said. I see that the relay is for switching AC loads. So I stand corrected, it won't work.

duh. i have a spdt 5vdc relay that i am trying to use to send out a +12v signal when activated