LED Display Power Distribution: Cable Sizing for Video Walls
Practical guide to sizing cables for LED display installations. Covers power supply distribution, daisy-chain limits, and avoiding brightness variation.
The Unique Challenge of LED Displays
Large LED displays present unique power distribution challenges: they are extremely sensitive to voltage (a 5V rail that drops to 4.5V causes color shift), draw high current (individual panels 5-15A), require power distributed across large physical areas, and any voltage variation is immediately visible as brightness differences.
Power Requirements by Display Type
| Type | Pixel Pitch | Current/Panel | Typical PSU |
|---|---|---|---|
| Indoor rental | P3-P4 | 5-8A | 5V/40A |
| Indoor fixed | P2-P3 | 8-12A | 5V/60A |
| Outdoor | P6-P10 | 10-15A | 5V/80A |
Cable Sizing for 5V Systems
5V systems are extremely sensitive. A 0.25V drop = 5% — enough to cause visible dimming.
Example: P8 panel drawing 12A at 5V, 3m from PSU, using 2.5mm² cable:
Upgrading to 6mm²: V_drop = 0.22V = 4.4% — still marginal. For 5V systems you often need surprisingly thick cable.
Daisy-Chain Limits
Many LED panels support daisy-chain power, but each connection adds resistance. Maximum panels per chain: 2-3 at full brightness for 5V systems. For 48V systems, 4-6 panels per chain is acceptable.
Troubleshooting Common Problems
| Problem | Likely Cause | Solution |
|---|---|---|
| Dim edges | Voltage drop | Add dedicated cable runs |
| Flickering | Poor ground | Star ground topology |
| Color shift | Uneven voltage | Shorter runs or larger gauge |
| Panel resets | Voltage sag | Upgrade cable or add capacitors |
Use our Cable Cross-Section Calculator to size cables for your LED display installation.