Below, we provide the theory behind calculating for voltage drop and understanding what thickness of core cable is required for certain runs. If you prefer a quicker option, you can consult Solar-Wind's DC Cable Sizing Tool HERE!
Choosing the right size of cables is critical for the proper functioning of LED strip installations. Choosing the right core size of the cables avoids significant voltage drop to occur (up to 5% voltage drop, from the source to the LED strip is acceptable).
The core cross sectional area (mm2) of the cables, required for each installation is calculated using the steps listed below.
Step 1: Calculating the power consumption of the LED strip
Determine the length of the LED strip and calculate the power consumption of the LED strip by multiplying the power by the length of the LED strip as follows shown in equation 3:
Power consumption[W] = Length of LED strip[m] x LED strip power per meter[W/m]
Example: Power consumption = 5[m] x 14.4[W/m] = 72[W]
Step 2: Calculating the current (I) of the installation
The maximum current (I) passing through the LED strip is calculated using equation 4.
Current (I)= Power consumption (P)Voltage (V)
Current (I) = 72[W] / 24[V] = 3[A]
Step 3: Calculating the cross-sectional area of the cables
The required cross section area depends on the length of the cable required and it is calculated using equation 5. The result should be rounded up to the next standardised cross-section area cable, available in the market.