Power Injection

Intro

When working with low voltage (5VDC and 12VDC) LEDs and Pixels it is common to have to add power injection to the end of long strings of lights to overcome voltage drop caused by the high current used by the LEDs over the small wire that is commonly used. A classic symptom of the voltage being too low at the end of a pixel string is the pixels may look Pink instead of White when turned on fully White. If the color of the first pixel in a string is different from the last pixel in the string, it is likely due to the voltage drop in the string and the wires supplying it. Other symptoms of too high of a voltage drop in a system are: random flickering, Pixels not responding to signals, and poor color lighting.

Using a formula called Ohm's Law you can calculate the effect of the voltage drop by entering in the wire size and the power drawn by the LEDs or Pixels. It is important to choose the correct Wire Size for your layout to minimize voltage drop. There are online tools like the Voltage Drop Calculator that can assist you in calculating the impact of the wire size vs. power needed.

Disclaimers

The standard disclaimers pertaining to the information contained on this wiki page are listed here.
THIS WIKI PAGE IS NOT COMPLETE YET AND HAS NOT BEEN CHECKED FOR ERRORS.

General Rules

• Always use the proper size fuses and fuse holders to protect your system from damage.
  • Install Fuses between Power Supplies and Controllers
  • Install Fuses between Controllers and Pixels or LEDs (If output fuses are not installed on the Controllers)
  • Install Fuses between Power Supplies and Power Injection Wiring.
• Use the largest diameter (smallest AWG wire gauge) that you can to minimize voltage drop to circuits.
• DO NOT TIE TOGETHER POSITIVE (V+) OUTPUTS FROM DIFFERENT POWER SUPPLIES!!
• DO TIE TOGETHER NEGATIVE (V-) OUTPUTS FORM DIFFERENT POWER SUPPLIES AND PIXEL CONTROL SIGNAL FEEDS.
• Only connect one power supply to each LED or Pixel string.
• Using the correct Wire Size will often allow you to use up to 50 5VDC Pixels and 100 12VDC Pixels without Power Injection.
• Choose Power Supplies that have have a high enough current rating for your system.

Pixel System Power Components

• Power Supply
• Power Supply to Pixel Controller Power Wiring and Fuses
• Pixel Controller
• Pixel Controller to Pixel Power Wiring, Pixel Connectors and Fuses
• Pixel String Wiring
• Power Supply to End of Pixel String Power Injection Wiring and Fuses

Related Links

Different Styles of Pixels
Controllers
Dumb RGB or Intelligent Pixels??
Things You Will Need To Get Started With Pixels
Pixel Wiring Colors
Pixel Connectors
Choosing a Pixel Voltage: 5V vs 12V
Power Supplies