12v DC and cheap stuff...

I hope I can make this simple and sweet… I’m controlling 8 12v RGB LED strips [Each <24" in length] with PWM through tip120 transistors, over 14’ CAT5 patch cables. The prototype had no problem driving 3 of these, but my question is regarding the RJ45 jacks themselves. In sourcing the 16 PCB jacks I need, I came across a very good deal for 8P8C CAT3 jacks. At most, on full white, the LED strips could draw ~1A each on the largest strands.

In short: Will there be any trouble (cable/jack damage or melting) with running 12v1A through CAT5 cabling that is terminated at each end by CAT3 jacks?

These connectors are not rated for high current. But as they are used for Power Over Ethernet, they can handle a moderate current. I think 1A would be on the high side especially if being passed through a few wires at the same time.

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OK, noted... Being RGB LEDs, the 3 wires would carry ~0.4A/ea per meter (all strips are about 2/3 this length or less) if on full-white. I should probably note that the LED strips will only be on in short bursts, 2sec at most, and almost never full white. I have full confidence in the cabling be able to handle the current, I'm just wondering if the jack being rated CAT3 has any implication in this, as it is purely analog and no data transmission is taking place (taking bandwidth out of the question, which is all I can seem to find anyone discussing on various sites when researching this).

In your use, it is just a piece of wire so treat it as such. The connectors will probably survive your use.

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