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Discussion Starter #1
I'm driving 25ft of LED 5050 LED tape lights using a 60w 12v 5a power supply. I noticed the first section is extremely bright, following the next section, the light gets dimmer, the next section gets even dimmer than the last.

The led are joined using solder wire in some and the other section I use the original joining clips.

Assume I'm loosing voltage down the string and the PS is probably running over its max capacity. If I upped it to a higher wattage PS, will it fix my dimming issue?
 

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Probably not. If the power supply was fading all the LEDs would be dim not just the last ones in the string. You are getting voltage drop within the strips. You could try feeding the LEDs from the center out instead of from one end.
 

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Discussion Starter #3 (Edited)
Probably not. If the power supply was fading all the LEDs would be dim not just the last ones in the string. You are getting voltage drop within the strips. You could try feeding the LEDs from the center out instead of from one end.
problem is my LED is used outdoor around the retaining walls. Driving it from the center will require a very long drill bit to go through 8" of masonry bricks.

Any other suggestion to reduce the voltage drop?

I googled and saw some recommend a higher voltage ps and then a step down regulator...not sure how this would help.

I do have an open end on the opposite end. Would it help if I ran a wire across and tap into the other side as well driving the strip from both ends?
 

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take a voltage measurement at the last string.
See how much voltage you are loosing
Boost the input voltage by this amount
So that the end string gets correct voltage.
You now go to the middle string measure the voltage there
It will be slightly high, use a resisitor to drop this down.
Ditto with the first string.

If you do not know how to choose your resistors ?
then post the voltages on here
And we can help choosing them.

This idea will work
But I do not know what code issue's will arise if any ?
 

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Discussion Starter #5
take a voltage measurement at the last string.
See how much voltage you are loosing
Boost the input voltage by this amount
So that the end string gets correct voltage.
You now go to the middle string measure the voltage there
It will be slightly high, use a resisitor to drop this down.
Ditto with the first string.

If you do not know how to choose your resistors ?
then post the voltages on here
And we can help choosing them.

This idea will work
But I do not know what code issue's will arise if any ?
great idea, i'll take some measurements in the morning.
 

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This is a common problem as the conductors in the tape lights aren't anywhere near heavy enough for the job. The voltage drop over the length of the tape leads to the next tape having too low a voltage. Stepping up the supply voltage won't help. You'll still have the voltage gradient as you go down the line.

Light manufacturers make tiny DC-DC step up power supplies that fit between tapes and boost the voltage back up to the expected level. They're annoyingly called 'amplifiers'. Search on Amazon for "LED amplifier" and you'll come across many examples.
 

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Run a pair of 14 gauge "backbone wires" from the power supply to the beginning of the farthest LED strip, following the routing of all the strips in order.

Connect each LED strip to the backbone wires instead of end to end to each other.

When cutting away a half inch or so of insulation cover on a backbone wire to provide an attachment point for a lead from an LED strip, be careful not to nick the copper wire inside.
 
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