RGB LED Strip - Red Light not working after connecting the 2nd strip with Amplifier

Thread Starter

sashtaneja

Joined Nov 23, 2020
8
Hi there!

Okay so I have 2 RGB LED Strips connected with a portable RGB LED Amplifier but I cannot get the red light to work on the second strip. The Blue and Green ones do work flawlessly on the 2nd strip.

Things to note:
- I've used 2 power supplies (12V, 2A) - one for the first strip, and another for the LED amplifier.
- I've tried with not 1, not 2, but 3 separate amplifiers but the red light on the 2nd strip NEVER works when connected with the Amplifier.
- The Red light on the 2nd strip DOES work when I connect the 2 strips without the amplifier (and yes the brightness does reduce in the 2nd strip).

I'm using the following LED amplifier and the connection diagram is as follows.

Any ideas why this is happening or how can I fix it?

Much appreciated!

DC12V-3-4A-144W-Mini-Portable-RGB-LED-Strip-Amplifier-Repeater-For-LED-Strip-RGB-SMD.jpgScreenshot 2020-11-24 at 4.58.20 AM.png
 

ElectricSpidey

Joined Dec 2, 2017
1,385
I assume the controller is PWM, and the amp simply returns the voltage back to 12 volts at the same PWM as the controller.

You might try bypassing the red connection across the first strip. (a kludge for sure)

Sounds like the amps are duds.

But, first try placing one of the amps before the first strip.
 

Thread Starter

sashtaneja

Joined Nov 23, 2020
8
I assume the controller is PWM, and the amp simply returns the voltage back to 12 volts at the same PWM as the controller.

You might try bypassing the red connection across the first strip. (a kludge for sure)

Sounds like the amps are duds.

But, first try placing one of the amps before the first strip.
Thanks for your reply. Not sure if controller is PWM but it's the standard, basic one that comes with a 5-meter LED strip pack. For the sake of it, I just changed the controller to an expensive, Wi-Fi based (alexa-enabled) one but still see the same issue.

Also, to add, the amps I bought were from 2 different sellers on different websites - all are perfectly new, so am assuming they're not an issue.
 

ElectricSpidey

Joined Dec 2, 2017
1,385
Judging from your first post I doubt if the problem is the controller.

I would still try hooking one of the amps before the first Led string, just to be sure the red red works that way.
 

Thread Starter

sashtaneja

Joined Nov 23, 2020
8
Judging from your first post I doubt if the problem is the controller.

I would still try hooking one of the amps before the first Led string, just to be sure the red red works that way.
Okay, just to clarify - you're suggesting to add an amp after the controller and before the first strip, and use a third power supply for the additional amp, correct?
 

ElectricSpidey

Joined Dec 2, 2017
1,385
No, don't hook up the second strip, just confirm that the red works with the amp connected directly to the controller.

1 power supply
1 controller
1 amp
1 strip
 

Thread Starter

sashtaneja

Joined Nov 23, 2020
8
No, don't hook up the second strip, just confirm that the red works with the amp connected directly to the controller.

1 power supply
1 controller
1 amp
1 strip
Just tried it. None of the lights in the LED strip work that way.
Power Supply > Controller > Amp > Strip > No light at all.
I think the amp does need its own power supply.
 

ElectricSpidey

Joined Dec 2, 2017
1,385
Ok, so at least the amps work with a higher voltage.

Possibly you could try using 2 amps, one before the first strip and one after. (yes, 3 supplies)

Seems like something you shouldn't have to do...right...

How much current do the strips require, perhaps you could use the same supply for both amps?
 

Thread Starter

sashtaneja

Joined Nov 23, 2020
8
Ok, so at least the amps work with a higher voltage.

Possibly you could try using 2 amps, one before the first strip and one after. (yes, 3 supplies)

Seems like something you shouldn't have to do...right...

How much current do the strips require, perhaps you could use the same supply for both amps?
Not sure about the amperage requirement for the strip, but I believe they're the basic 60LED/m 2835 RGB LED strips.

I currently don't have a 3rd power supply or adapters to hook 2 amps to 1 power supply (am using the ones came with the strips - the 12V, 2 pin wall bricks with male jack connectors).

But yeah I'll arrange a third one and test it soon - 2 amps for a 2-strip setup - lol yeah it does sound redundant, but whatever works.

In the end, I actually need to hook 5 strips together that work in sync for my ceiling. Been trying to build something like this:
https://www.dropbox.com/s/zx1dqzzc8j7l21f/Screenshot 2020-11-24 at 6.31.33 AM.png?dl=0
 

Thread Starter

sashtaneja

Joined Nov 23, 2020
8
Ok, so at least the amps work with a higher voltage.

Possibly you could try using 2 amps, one before the first strip and one after. (yes, 3 supplies)

Seems like something you shouldn't have to do...right...

How much current do the strips require, perhaps you could use the same supply for both amps?
Okay I tried this - 3 power supplies, 2 amps and 2 LED strips. Still saw no RED in the 2nd strip. Tried interchanging the power supplies and the LED strip positions as well but no luck.
 

ElectricSpidey

Joined Dec 2, 2017
1,385
Well, that probably eliminates the possibility of chaining the strips using those amps. (unless we are missing something obvious)

Another option might be putting the amps in parallel from the controller and running cables to each strip. (another kludge)

So you would need a splitter at the output of the controller.

One caveat, if the input impedance of the amps is not high enough, that might not work either.

It's obvious the amps are not doing what they are designed to do, so you can continue to try and "fix" the issue, or go a different route.
 

Thread Starter

sashtaneja

Joined Nov 23, 2020
8
I've been able to solve the issue by using a splitter cable. I have absolutely no idea how a 1 to 2, four-pin splitter did it, but all the amps work now and the RED light does glow in the consecutive strips! Wohoo!

Power Supply > Controller > Splitter Cable > 2 Strips in parallel > Amp(s) with power supplies at the end of each strip > More Strips in series

I couldn't put all strips in parallel because then I'd need to use a big power supply to keep in the ceiling (where I'm installing the lights) where I don't have enough space for it, but using just 2 strips in parallel using a splitter, and then powering the rest in series gets the job done. But thanks @ElectricSpidey for sticking with me and helping out with experiments. I'll install all the lights soon! :)
 
Top