DMX 512 RGBW Constant Current 700mA LED Controller

Modified on Mon, 5 Jun, 2023 at 2:36 PM

How can I determine the maximum cable distance for my CAT5e wire setup with RGBW spotlights?

In any setup where multiple spotlights are connected to a single LED controller, there are two important factors to consider: the resistance of the wire and the voltage drop across the LEDs (referred to as "VF").

If you're using a CAT5e cable (which has a 24 AWG single core), the resistance is approximately 0.2 ohms per meter. Now, let's say you connect 8 of our RGBW spotlights (which operate at 700mA each) to one LED controller. The total VF for these 8 spotlights is 28V. This means that the combined operation of the 8 spotlights requires a total of 28V (each spotlight requires approximately 3.5V to operate, so 3.5V times 8 equals 28V).

Given that the output voltage of the driver is 48V, you can determine the maximum total cable distance for this setup by subtracting the total VF from the driver output voltage, and then dividing the result by the resistance of the cable.

Applying the numbers to the formula: (Driver Output Voltage - Total VF) divided by Cable Resistance equals Maximum Cable Distance.

So, if we plug in the given values, we get: (48V - 28V) divided by 0.2 ohms equals 100 metres.

In this example, the maximum total distance of all cables in this chain would be 100 metres.

Please bear in mind that the above example and the resultant 100-metre distance is calculated based on using 24AWG CAT5e cable. This calculation is underpinned by the cable having a single core with a resistance of approximately 0.2 ohms per meter, which is characteristic of 24AWG core. Therefore, it's critical to check your own cable to confirm it meets this requirement. If your cable differs from the 24AWG specification, then the maximum cable distance could vary. Always ensure to validate the AWG of your cable before conducting any calculations or installations. If you're in any doubt, do consult with a qualified technician or cable manufacturer for further assistance. Remember, the quality of your installation depends heavily on the quality and specification of your cable, so it's essential to get it right.