3528 LEDs, Soldering & Insulation

[Belial88]

edit: I have a long LED strip set up (multiple soldering points to attach multiple sections, bends, etc). 3 of the lights, ie a single section, in the middle of a section, isn't lighting up (it will with a bit of twisting and such of the strip).

If it was bad wiring, wouldnt the rest of the line not light up? If it as bad lights, all in the same section is quite a coincidence. Can I fix this somehow? It would be a HUGE pain to have to remove and attach new line there...

Thanks.

 

[aigomorla]

i assume u got the strip and not the individual leds?

u can just attach the strip under using double sided sticky tape.

i still used a thin sheet of acrylic tho....

if u got the individual LED's... mmm... ur gonna need resistors on top.
Or your gonna need to wire a couple in serial to get them to light @ 12V and not blow.

 

[Belial88]

Sorry for not being clear! I bought 2x 5meter rolls of 3528 60LED per meter (ie the higher density version, non-waterproof ofc).

Specifically, what I am doing is laying 3528 blue LEDs on my bitfenix shinobi where the wire mesh strips are. I'm putting parchment paper behind the strips to diffuse the light (to avoid the spotty-affect of LEDs, and it does a damn fine job after initial tests!), to achieve the following affect:

The top panel (which disconnects like a front panel), unfortunately, has it's mounting holes right along where I'd lay down the strips so as to be right behind the wire mesh, so I've had to do quite a bit of soldering (ie LED - 2 wires which I bend to go around the peg - LED - 2 wires - LED, etc). I just wanted to make sure there was no issue of like, the soldering work or wires attaching to the 3528's causing a short when laid against a computer case.

Common sense would tell me... well, that it would short, but I haven't heard anyone mention this before. But okay, wrap the soldering/wiring up with some tape, derp.

 

[Belial88]

Okay new question -

I have a long LED strip set up ~ 3m cumulative (multiple soldering points to attach multiple sections, bends, etc). 3 of the lights, ie a single section, in the middle of a section, isn't lighting up (it will with a bit of twisting and such of the strip).

If it was bad wiring, wouldnt the rest of the line not light up? If it as bad lights, all in the same section is quite a coincidence. Can I fix this somehow? It would be a HUGE pain to have to remove and attach new line there...

There's also another 3 led section that flickers, but it seems to be okay if i hold it down flat. I don't think I'll bother replacing that as hopefully it'll be fine when it's put where it's put.

It acts this way both on a 12v 1.5a wall wart and hooked up 12v psu.

 

[aigomorla]

These leds were designed to run on cars with 12v.

It should have no issues running on a pc psu.

Did u get the correct solder points?
Or did u miss cut at a joint?

 

[Belial88]

If there was an issue with a connection/soldering, don't you think the entire section would be off?

Like I have a strip with like 10 sections soldered together, each section held together by wire ~1-4inches long. Some sections are only ~3inches long, others are 1m. The part with 3 LEDs that are off, is one of the 1m long sections, also one of the first sections in terms of contact (ie psu -> long section with 3 leds / 1 3-led part not working etc...). And now the next 3 LEDs on that section seem to not be working...

As painful as it is, I think I'm going to have to excise that bad piece (now 2 pieces...) and solder a replacement on. I tested the voltage with a multimeter on those contact points every 3 LEDs, and the voltage seems to be there on all of them. I have no idea what the issue is, when I twist it a bit sometimes they come on.

I have a separate question though: I bought SPST switch (2 contacts, it's a simple switch that stays up or down) to turn the LED on/off. Can I connect it in the middle of the LED lights? like instead of psu, red wire to contact 1, then contact 2 red wire to accessory, go like led strip -> red wire to contact 1, then contact 2 red wire to led strip?

 

[Belial88]

Up

 

[Belial88]

Hm I'm a bit of difficulty with these LEDs. 1 3-led section stopped working and another was flickering, now another strip has 4 led's not working and another 3-led section blinking.

I checked the voltage on the 12v 1.5a wall wart I'm using with a multimeter, it's 11.8v, so nothing should be wrong there (I've also used my PSU's 12v lines a few times).

Is this common? Why is this happening?

 

[Vinwiesel]

I am guessing that the strip is a series/parallel circuit. So for 60 LED's, there would be 20 sets of 3 led's. If each set of 3 led's is in it's own circuit, one of the 3 could be bad and all 3 would not light. Since some of them work when flexed it sounds like a connectivity issue which could be in the wiring of the strip, or in one of the led's itself. You might be able to fix the bad connection with soldering, or adding a jumper wire but it would require a good understanding of how the circuit is laid out.

It is not uncommon for a led to become intermittent after being overheated or over-driven.

 

[Belial88]

Well if it's a flex thing, then that would be the pcb-strip wire that it's in. I'm not sure how you would get to soldering that (even if you did, no more flex, which i guess doesn't matter in my application).

Anyways, it was right off the bat so I'm getting a replacement roll. I also finished up all the LEDs and stuff, i can't upload pics atm but I will. It's pretty insane looking. I hooked up a SPST switch so i can turn the LEDs off/on.

I mean it's more than lights under the case like a car. I put it on all 4 edges on the bottom, so it's not just the sides, but front/back. The strips on the mesh, I used parchment paper to diffuse the light and it looks great, and I put parchment paper on the logo which is catching more than enough light to light up great too.

It's seriously insane looking.