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There is a question on a 1m set of WS2812B LEDs at 144 LEDs/meter (60mA/LED at peak brightness) about what gauge wire is used. The seller replies that the wire is 22 AWG (linked above).

144 * 60mA = 8.6A

If this wire gauge chart is reasonably accurate, then it's not clear to me how a device that is designed to consume 8.6A at peak is appropriate for 22 AWG wire. Shouldn't it have 20AWG wire or better? What am I missing?

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    \$\begingroup\$ Are the LEDs in parallel, or are they in series? \$\endgroup\$
    – Hearth
    Oct 3, 2018 at 21:28
  • \$\begingroup\$ In the strip itself, the power to the LEDs is parallel. (The data wire is in series, on the other hand.) At least, this is my best understanding of the configuration. \$\endgroup\$ Oct 3, 2018 at 22:05
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    \$\begingroup\$ That question is generic to the listing which also covers 60 leds per meter. \$\endgroup\$
    – Passerby
    Oct 3, 2018 at 22:49
  • \$\begingroup\$ @Passerby good catch. I've submitted a follow-up question on Amazon to try to get clarification for the 144-LED model specifically. \$\endgroup\$ Oct 3, 2018 at 22:52
  • \$\begingroup\$ FYI, Amazon informed me that there were no replies to my inquiry. \$\endgroup\$ Oct 6, 2018 at 14:08

2 Answers 2

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You are right, it should not be using 8.64 amps or 43 watts with a single 22 AWG wire.

Of course, that 144 led strip looks like it has two power and two ground cables of 22 awg, doubling the copper and essentially having the same capacity as 19 awg wire. So those wires themselves would be fine.

enter image description here

You also have to factor in the high resistance of FPC. Even if those 144 leds are all full on white, you will likely see the far end being dimmer, and the overall current draw will be less than the theoretical 8.64 amps, even at only 1 meter.

Good rule of thumb, is inject power every 2.5 feet if you can, or both ends of a 5 foot led strip.

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I would say that running 8.6A (even with one stand-alone conductor in free air) through a 22AWG wire is a bit risky. Try downloading the free "Saturn PCB tool kit" from www.saturnpcb.com for more reference on many disciplines would perhaps be beneficial.SaturnPCB Tool Kit

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  • \$\begingroup\$ Your concern seems right. It's just very odd to me that this is the wire gauge that is connected by the distributor to a strip with these specifications! \$\endgroup\$ Oct 3, 2018 at 22:09
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    \$\begingroup\$ This seems spammy. And says nothing that OP's link doesn't already do. \$\endgroup\$
    – Passerby
    Oct 3, 2018 at 22:46
  • \$\begingroup\$ @Passerby. Don't judge a book by the cover...try it you might like it. \$\endgroup\$
    – Steve
    Oct 3, 2018 at 22:51
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    \$\begingroup\$ I do not think this is spam as this app has been around many years. But @passerby has a good point that it offers the same as the OP's post. Not being an answer, it does appear to only be plugging the app. \$\endgroup\$ Oct 3, 2018 at 23:22
  • \$\begingroup\$ @Passerby/Misunderstood. Fair enough. My intent was not to plug or spam, just giving the OP the tools to make an informed decision based on the off-the-shelf product. \$\endgroup\$
    – Steve
    Oct 4, 2018 at 18:53

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