Small electrical question, I know this isn't an RGB strip so pardon me.

(Franck Marcotte) #1

Small electrical question, I know this isn’t an RGB strip so pardon me.

I have this 24V strip 60/m 5730. I want to bring the density down to 30/m, I’m wondering if it’s safe to just remove half the leds from the strip. There is some kind of resistance every 3 leds (marked “390”).

Thank you

(Testi Cuss) #2

No. If you “remove half the leds” (and short their pads) then you will just make a 12V strip out of it - which may or may not be an acceptable compromise for you. But not sure whether the 39 Ohm resistor will still be appropriate in that case. I suggest you try it on a single cut segment (6-LED) first, instead of risking multi-segment fireworks :slight_smile:

(Kirill Kolyshkin) #3

Can’t see it from the photo, but usually leds in strips like this one are connected in series of 3 (plus a resistor), and you just can’t remove half of 3 leds. Hope this makes sense.

Can you please share why you want to remove half the LEDs? What are you trying to achieve?

(Franck Marcotte) #4

@Kirill_Kolyshkin I don’t need that much density for the project and I’m worried about heat dissipation since these won’t be mounted on an aluminum profile. They will be snaked through some kind of beaded strings, in an oval shape. Since I need to get this done with the material I have right now, I won’t take any chances and just use the full density dimmed. Thanks for your answers!

(Kirill Kolyshkin) #5

@Franck_Marcotte yes, I think that dimming (with PWM) is a great option.

(Kirill Kolyshkin) #6

@Franck_Marcotte in fact you can short-circuit say every third led (say a one near a resistor), and use 12V instead of 24V to power the strip. It should give something roughly close to half the full brightness.

(Franck Marcotte) #7

@Kirill_Kolyshkin I did a few more tests with the strips now that I got a PSU that does variable voltage from 0-24V.

These are the strips :

They are rated 12-24V. I played with my PSU and at 12V they are completely off, and they dim properly all the way up to 24V. Does that mean dimming them with voltage is safe?

Also, I let them run for a long time at full brightness and they barely get hot, and are very bright. So I think heat dissipation is less an issue thank I thought, since they won’t be encased. Looks like the strip in free air is doing alright.