12v power adapter

[greyphantom1000]

totally dumb question i think- it just accured to me that at the shop i work at we have 12v power incerters for a satalite tv box. If i snipped off the female connector at the end and soldered it to some led's, would this work the same as a 12v battery?

 

[TBadger]

You'd have to check all of the specs on your adapter and if they support DC....AC won't work for most LEDs without an inverter. I'm sure Grendels is much more knowledgeable, but I've learned the hard way not to just splice wires in to things they weren't meant for.

 

[greyphantom1000]

does this look right for led's?

[attachment deleted by admin]

 

[TBadger]

Considering most LEDs are 20mA and your adapter is 1.25A output.....I would warrant a guess and say no. Grendels could give you a more educated answer, but it looks like its set up for a much higher current draw rig. TVs, Cable Boxes and such. I'm sure it's possible to regulate the power supply, but it'd be more frugal and sensible to get a bench test power supply if you plan on doing a lot of electronics

 

[KA-22]

What is Big plan for Wall Adaptor? one time use ? Or more models will use same Wall wort?

From photograph you supplied! DC output is Good! Resistors will need to be applied to each LED to limit current from exceed 20ma. If your not use Current limiter resistor, burnt LED you will end up with!

http://www.hebeiltd.com.cn/?p=zz.led.resistor.calculator

Go there to get resistor value!

Gut lock!

Karl.

 

[Elm City Hobbies]

As long as he figures out the proper resistors for the LEDs using that AC adapter, he should be fine, but one with a lower amp output would be more desirable.

 

[greyphantom1000]

no big plans. We just have extra power adapters that will be thrown away. I thought if i were to do a diorama or something with a lot of lights i could use that

What is Big plan for Wall Adaptor? one time use ? Or more models will use same Wall wort?

From photograph you supplied! DC output is Good! Resistors will need to be applied to each LED to limit current from exceed 20ma. If your not use Current limiter resistor, burnt LED you will end up with!

http://www.hebeiltd.com.cn/?p=zz.led.resistor.calculator

Go there to get resistor value!

Gut lock!

Karl.

 

[Grendels]

Just getting caught up. Yesterday was very busy!

Yes that power adapter will work just fine for LED's. As the others have said, you will need resistors for the LED's or they will last about 1.3 seconds.

The one thing I would worry about is the output voltage. These types of adapters have specifications to them that allow for some tolerances in the voltage. So it might be listed as a 12V output, but if the tolerance allows for +-15% it could actually be outputting 13.5 V or 10.5V. If it has a high output, you will just burn up every LED you hook up to it.

I would invest in a multi-meter pretty fast if you are getting into working with LED's. That way you are sure of your voltages and your resistors. Also, if you continue to work with electronics, a bench power supply will become a happy option soon.

 

[greyphantom1000]

i am envious of your bench poweer supply john... thanks for the help!! no worries we moved into our new house a year ago and i know how much time it takes up. thank you sir!

 

[Grendels]

I just took a look at my post and realized that I didn't explain part of it. Make sure you measure the voltage output of the wall wart. That is where the multimeter will come in handy. On the Mercury 9 I decided to measure that output and found it was far outside what the specification stated on the plug. I went to a more expensive option and it holds the voltage where it is suppose to.