Question

I am doing a project where kids can follow a light around a map. I am using 300 ws2812b led light strips with a 5v 60amp power supply and a raspberry pi. When I attach the 300 lights to 50ft of 18 gauge led wire it works find. But I need this trail to be 31ft so I cut the strip into 10 led blocks and put a piece of wire between each block expanding it to 31ft. I can get the lights to work for a little bit then they start acting really crazy. Does any one know what I’m doing wrong? I would appreciate any helpiCloud link for a video of problemAnother video I have of the issue

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Here are some thoughts and suggestions:

Does it always malfunction in the same general area?

Looking at the datasheet, the whole strip could be using close to 6A. If the wire soldering doesn't have a good connection, you would have increased resistance, hence an increased voltage drop along the way. The first segments are most solicited and the quality of the soldering there matters most.

The datasheet also mentions that the led's need 6-7 volts. They apparently work with 5V, but with the increased resistance of the wires, it looks like it's dropping below a functional level.

Suggestions:

  • Check the voltage on the segment in the area where it starts malfunctioning and compare it to the voltage of the first segment.
  • If you have an oscilloscope, look at the data line in the problematic area as that may give you some indications about what is happening.

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>> I can get the lights to work for a little bit then they start acting really crazy

It might even be possible that the current is heating the wires (which might take a couple of seconds), which increases resistance to the point where it fails.

If so, it might work on a cold day and fail in the sun... maybe a parallel power supply wire could stabilize it.

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22 minutes ago, xc6lx45 said:

>> I can get the lights to work for a little bit then they start acting really crazy

It might even be possible that the current is heating the wires (which might take a couple of seconds), which increases resistance to the point where it fails.

If so, it might work on a cold day and fail in the sun... maybe a parallel power supply wire could stabilize it.

Thank you for your input. Do you think I should add another 5v 60a power supply to the end of the strip?or should I run another wire from the 5v60a power supply to the end?

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3 hours ago, vicentiu said:

Here are some thoughts and suggestions:

Does it always malfunction in the same general area?

Looking at the datasheet, the whole strip could be using close to 6A. If the wire soldering doesn't have a good connection, you would have increased resistance, hence an increased voltage drop along the way. The first segments are most solicited and the quality of the soldering there matters most.

The datasheet also mentions that the led's need 6-7 volts. They apparently work with 5V, but with the increased resistance of the wires, it looks like it's dropping below a functional level.

Suggestions:

  • Check the voltage on the segment in the area where it starts malfunctioning and compare it to the voltage of the first segment.
  • If you have an oscilloscope, look at the data line in the problematic area as that may give you some indications about what is happening.

Thank you for your input. I don’t have an oscilloscope. I have 4.3-4.7 volts throughout the cable

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17 minutes ago, David lebental said:

Thank you for your input. Do you think I should add another 5v 60a power supply to the end of the strip?or should I run another wire from the 5v60a power supply to the end?

I wouldn't put two supplies in parallel. If one short circuits the output for whatever reason (circuit fault or even self protection shutdown in some models), the cable would burst into flames.

Driving both ends from the same supply (possibly with an additional "fat" cable) sounds like a good plan. Or, run the additional cable in parallel with the strip and connect it at intervals.

Higher voltage seems also a good idea, but I haven't checked the datasheet.

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