how far apart can I have my neopixel rings without random color changes
It sounds like you are asking how long the signal line between two NeoPixels can be without getting errors. We have not characterized that and I suspect it will depend a good bit on your exact setup (electrical noise, power source, etc.). In general, I expect something around a few feet to probably be okay. How far apart do you want them?
The manufacturer of the Neopixel rings, Adafruit, might also have more information.
I have a ten amp power supply, 16/4 wire between each 16 LED neoPixel ring
I have tested with 25’ from Arduino to the first and 25’ to the second and it works but by the time I add a third 25’ to that next ring, when I send a blink red command, the second and third ring look fine but the first blinks random colors.
Thanks for your help, I’ll try checking with Adafruit
I know that Adafruit specifically recommends keeping the distance between the Arduino and first LED as short as you can. I think the recommendation was a few feet maximum. If you can’t move the first ring any closer, you might also try using some individual NeoPixels as decoy/buffers in between your rings. For example, using an individual pixel that is set to not light up every 5 feet between rings to help boost the signal.
How many rings are you planning to use? I would love to see what your project is!