Hello everyone, I am not an electrician I am a glass manufacturer however in my spare time I have a project that I need some help on. I have searched through the forums and found a couple similar posts but these were not particularly clear for my understanding.
(please help with this simple LED strip project! by daveym)

I have not bought any materials to complete this project, because I want to make sure that my materials are exactly what I need. According to the research I have done the materials that I think would best suit my purpose are as follows

Deep Dream UV Black Light Led Strip 16.4Ft/5M 3528 300LEDs Flexible Waterproof IP65 BlackLight Night Fishing Sterilization implicitly Party with 12V 2A Power Supply

Gardner Bender GSW-25 Maintained Contact Push-Button Switch, SPST, ON-OFF

Bosch Cord 120V

Are there other materials I need?

What I am trying to accomplish is to illuminate a painting with an led black light strip.
I plan to attach 4 black light led strip segments to the inside of a picture frame (two 5 inch lengths and two 7 inch lengths), cut from a 16.4 foot reel, with an on/off button attached to the side of the frame. With a 5 foot power cord connected, I was thinking about using a 120v (USA standard) household plug , is that overkill? Is there a better way to supply power from a standard (USA) outlet?

I plan on soldering wire to connect the 4 led strips together, what gage would be needed? I was thinking that I might need 10ga-12ga copper but I am not sure.

Are there other items that need to be added to make this work?

Once I have the 4 strips connected, can I wire positive/negative to the button, then wire it to the 120v plug?

Is there a better way to do this project? Attached to this post is what I currently have for a wiring diagram. Thank you in advanced for your help.

 

While the LED strip link does not mention the current, rest assured you will not need AWG 10 or 12 wire. The power supply is 12 Volts at a few amps max and taking a wild guess I doubt you will need anything but common hookup wire or AWG 20.
You would just use a standard line cord and plug, line cord likely AWG 16 is common. The 12 Volt 2 Amp power supply is not going to draw any power to speak of. Then you only need to switch the (+) connection so from the Neg (-) of power supply to the Neg of light strip and switch the pos. What you have drawn should work just fine. The included power supply may include the line cord for power?

Ron

 

Thank you for the quick response, you have been quite helpful. I understand everything up until

Then you only need to switch the (+) connection so from the Neg (-) of power supply to the Neg of light strip and switch the pos.

Are you saying that I need to switch the positive connections?If so then what am I supposed to switch the positive connections to? Wire positive of household plug to positive of button, negative of household plug to negative of button, positive of button to positive of light strip, negative of button to negative of light strip? Sorry for being electrically illiterate, I am unsure of what you mean by

switch the pos

, switch the positive of the light strip to what? Again, thank you for your response.

 

I could have worded that better. Just connect the included power supply to mains power. Now on the 12 Volts out of the power supply connect the Negative to the Negative of the LED strip. You only need to switch the Positive out of the power supply so power supply positive out to your switch and the out of the switch to the positive of the LED strip. So in effect you are only switching the positive 12 volts to the LED strip. I could make a drawing if you like.

Ron

 

Here is a rough schematic.


Ron

 

I understand now but I want to be sure, going off your schematic I will need the power cord 120 VAC hot and neutral wired into a 12V power supply/transformer? From there I understand now that the positive from the power supply goes directly to the switch, then to the positive side on the led strip whereas the negative goes straight to the led strip since it does not carry a current and does not supply power. So I cannot directly wire a 120 VAC Mains power plug to the switch (positive to switch negative to led strip) and have it operate off of a household outlet? Your schematic makes perfect sense I'm just wondering what would happen if there was no power supply between mains power plug and the switch. I really appreciate you taking the time to help me better understand this, thank you Ron.

 

I am planning on making multiple of these and there is only 1 included 12v 2a power supply, for the next one I make I will have to buy another 12v 2a power supply and wire the plug to the power supply, positive to switch negative to led strip, positive from switch to led strip, is this correct?

 

I am planning on making multiple of these and there is only 1 included 12v 2a power supply, for the next one I make I will have to buy another 12v 2a power supply and wire the plug to the power supply, positive to switch negative to led strip, positive from switch to led strip, is this correct?

Yes, you'll need separate 12V power supplies for each one.

If you wired 120VAC directly to the LED strips, you'd burn up one or more components on the strip and create a fire hazard and/or shock hazard.

If you're only making small assemblies of short strips, and each one uses its own, dedicated power supply, you can probably get 1A or even 500mA supplies instead of 2A supplies.

 

Here is what I would do. Make the first unit as described as a proto type and make sure it works as advertised. Place everything on a bench (table top) and see if it does what you want. Then for the additional power supplies I would look to what we call a 12 Volt Wall Wort for the additional supplies. There is a good possibility you may only need 12 Volt 1 Amp power. The wall wort versions are convenient and plug right into the wall.

Ron

 

The wall wort versions are convenient and plug right into the wall.

If the pics on the Amazon listing are accurate, that's what's included with the LED strip as well. Doesn't look like there should be any mains wiring to deal with at all.

 

If the pics on the Amazon listing are accurate, that's what's included with the LED strip as well. Doesn't look like there should be any mains wiring to deal with at all.

That would be nice as I couldn't tell but sort of figured when they mention power supply it would include the line cord or be like a wall wort.

Thanks
Ron

 

Thank you ebeowulf17, is there a formula to figuring out exactly how many amps I would need? I understand that I should probably get a power supply that powers a little above what I need so I can avoid shorting anything out. Will it matter how the LED strip is wired together depending on whether its wired in parallel or serial? Or will it be positive to positive negative to negative like normal? I am going to call the manufacturer to figure out whether the led strip is wired in parallel or serial.

Since it appears that there is an included wall wort, I simply need to cut off the end with the circle plug, strip the wire and wire it to the switch and the LED strip? Or would it be best to not damage the wall wort, and simply plug the ends together? But on the next one that I make out of this same reel, I will not have either wall wort connector so at that point I will need to go buy another 12v 2a wall wort plus its female counterpart so that it has something to plug into? Would I then wire that female counterpart into the led strip at the point I had cut off before to allow a connection with the wall wort?

Again, I want to thank both of you for taking the time to respond and help me out. You guys have been extremely helpful

 

When you get the LED strip it will be on a roll similar to the below image. I say similar because the image is a RGB (Red, Green Blue LED Strip and thus 4 terminals. The strips are normally coated with a silicon coating and have an adhesive backing. You will see points with small copper solder tabs where the sections can be cut. Yours will likely only have two tabs a (+) and a (-).


Once cut to length use a sharp Exacto type knife to cut off and remove the silicone over the copper solder tabs, you cut right down the center of the tabs. Trim away the silicone above the tabs making sure it is removed and the surface is nice and clean. If you are not experienced soldering I suggest you find something to practice on. With the silicon removed you should have similar to the below image.



Again you will only have two tabs, likely labeled +12 and - 12 or similar. Your strings will be connected in parallel meaning + to + and - to -. Again, I suggest practicing soldering which is just an acquired skill and building the first round on the bench top.

The only way to know what the current draw is would be to measure it. Lacking that capability is just pure guess but I doubt based on your explanation you will exceed 2 amps and I doubt an amp actually. Less a good DC current meter there is no way to know as looking at the data sheet for your string I see no mention of LED Forward Current.This chart may help. A very rough guess and pure speculation is 0.020 Amp per LED and again I really don't know less a data sheet for those specific LEDs.

Yes, you can cut the leads on the wall wort output and solder to your first strip. Also, buy some silicon paste so once you solder you can place a small dab of silicon over the tabs to protect and prevent corrosion. After soldering a soft toothbrush and isopropanol alcohol can be used to clean the soldered surfaces. Small tubes of clear silicon can be had in any hardware store.

Ron

 

Wow that was everything I needed to know and in great detail, thank you for the pictures as well they helped a great deal. I have no further questions, if I do however run into a snag I will be sure to come back. I've got about 500 feet of wire to practice soldering together, I'm sure I could also find a bread board somewhere and practice on that.

Thank you Ron and ebeowulf for your help.

 

Anyone here is always happy to help and if you hit a snag don't hesitate to return with questions.

Ron