Controller Wiring Difference


New elf
Sep 29, 2021
I was looking at some designs for controller/power supply housing, and I came across two different power wiring types. 1: The power going to the pigtails is run right of the controller. 2: After going through a fuse block, the power runs right into the pigtail, and leaves an open terminal on the screw terminal on the controller. The picture below has both. What is the difference between the two? Does it effect the brightness or distance the power can travel? Thanks!
Screen Shot 2021-10-05 at 9.29.13 PM.png


Slightly unhinged elf
Aug 16, 2018
Either way will work and it doesn't effect or change brightness or distance.

As I mentioned in your other post current draw (Amps) is an important consideration for any design

Without knowing the total number of pixels connected to that board in the photo it's difficult to know the exact reasoning.

It's likely that the total current draw was too high so they split some of it off to another supply.

The secondary fuse block is likely for extra power injection points for longer strands of pixels.

Some people don't run any power from the controller and supply it all from separate supplies.

This hobby has a wrong way of doing something, a couple of right ways and a dozen partially right ways that still work but would make an electrical engineer cringe.
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Full time elf
Generous elf
Dec 27, 2014
Buellton California
Power inject or power through the controller. Could possibly be running 24v on the ones that are powered off the terminal blocks? I don't think F16 is rated for more than 12v. I find it much easier to power inject/use fuse blocks for the majority of my display. As @Grozzy mentioned lots of ways to accomplish the same task. People have different views and preferences on power inject or not to power inject, 5v vs 12v, etc. Lots of ways to accomplish the same outcome. Each bank of 8 outputs is only rated for 3o amps. 8 outputs with 5 amps exceeds that so that might be the logic as well. Hard to say the logic behind the build without contacting whoever decided to build it this way.


Retired Elf
Feb 9, 2020
West Central Ohio
In my opinion it relates (more or less) to the number of pixels that a port can drive logically to the number of pixels that can be powered from that port at the desired or required drive level. For example, a Falcon port that can drive nearly 1000 pixels (ignoring frame rate) will not power that amount without power injection unless the drive level is very low.

This leaves essentially 3 design choices: use a short string, power a string with power injection and the controller, or power inject a string with data only from the controller. Obviously displays and/or controllers can have a mix of these.