See full version: How many amps do 12 volt LED lights draw
One may also ask, how much power does a 12v LED light use? LED lights require far fewer watts of electricity from their 12V LED power supply to create the same amount of light; for example a natural white, high density LED strip light consumes 2.9 watts per foot, and produces 156 lumens per foot. A 40 watt white incandescent bulb produces about 500 lumens of light. more
A 12V/30 watt supply translates into a maximum of 2.5 amps of current drain (12V x 2.5A = 30 watts). [links]
Thereof, how many amps does a 12 watt LED draw? more
How many amps does a 4 foot LED light draw? here
How long is the length of LED strip you are connecting?
Which LED strip light product are you connecting? (Choose "3rd party" to input power specifications, if using a product not manufactured by Waveform Lighting)
Step 4: Find a power supply that has a wattage rating for more than 20% of the LED strip power draw calculated in Step 3. [links]
Because there are three LEDs in series, you cannot drive these LEDs from a 5V supply. The LED strips say "+12V" on them to mark the anode and that's the maximum voltage we suggest. We've found that if you're ok with them being a little dimmer, even 9VDC works very well.
Each segment of 3 LEDs draws approximately 20 milliAmperes from a 12V supply, per string of LEDs. So for each segment, there is a maximum 20mA draw from the red LEDs, 20mA draw from the green and 20mA from the blue. If you have the LED strip on full white (all LEDs lit) that would be 60mA per segment.
To find the total maximum current draw per meter, we would multiply 60mA x 10 (ten segments per meter for the 30/LED per meter strip) = 0.6 Amps per meter OR 60mA x 20 (twenty segments per meter for the 60/LED per meter strip) = 1.2 Amps per meter. Again, that's assuming you would have all the LEDs on at once and that you are powering it from 12V. If you're going to be PWM-fading between colors, maybe 1/2 of that is what you'll be drawing. Still, you do need to have a fairly decent power supply to run this strip, all those LEDs add up!
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This is where some math is going to be needed, but this math is even easier than figuring out the fifteen percent tip at restaurants, I promise! So let's say you've picked out a strip already. each strip also lists its power consumption in watts per foot. In our little hypothetical shopping scenario here, you'll be picking out the 5050 regular density strip, and you've decided that for your project you'll need thirty feet of lights. The 5050 regular density LED light strip is listed at two watts per foot, so for thirty feet of light, you'll be drawing sixty watts of power, and as it just so happens, we've got sixty watt power supplies!
That formula again : (Strips Wattage per Foot) x (Total Feet of Strip) = Total power required (Watts)
Well that's certainly possible, there are a few things you'll need to know. First off, you'll need to use a dimmable LED driver instead of a standard power adapter. Another thing to note is that using a wall dimmer and the dimmable LED driver will require you to hard wire the lights directly into the switch. That, or you'd need to wire your dimmer switch into a wall outlet and attach and AC power cable to your strips and dimmable LED driver and use that outlet. The last thing you'll need to know about wall dimmers and the dimmable LED driver is that RGB LED strip lights just don't have a good way to work with the wall dimmer. No cause for alarm though, as all of our RGB LED light strip controllers can dim our RGB LED strip lights, so you'll still be able to dim your lights!
Please do! Our 12V rechargeable battery packs for LED light strips are great for any mobile project, like Light Bikes or outdoor lighting that's not near any convenient power sources. So if you were planning a romantic picnic dinner in a field and candles aren't your thing? Then you should pick up a 12V rechargeable battery pack and a nice RGB LED light strip! 12V rechargeable battery packs are also great for boat lighting, assuming that the battery pack stays dry and your strips are rated for some to a lot of water! [links]