Question: Can someone clarify the colors on the simple air sensor? (turning white when plugged in)

stevie is asking a question about question
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by stevie | April 26, 2019 19:31 | #19173

I just heard this question from a community member::

"We are starting class presentations using the color-coded Plantronics units. One of them turns red for a second, then just white. Any ideas on how to fix?"


The #simple-air-sensor is supposed to show red-yellow-green, but I've seen them turn white when malfunctioning. Try unplugging it and plug it back in, and try a different power source. If it still doesn't work, can you upload a good photo of it so we can be sure it hasn't gotten unplugged or anything? Worst case you can send it back to us and we can send a replacement. Thanks!

There's a longer discussion about assigning colors to different levels here:

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Actually i just found if you force in the white connector on the side of the sensor, it's often the loose part and you can get the light to turn red/green again by pushing it in very firmly!

I'm not sure the white one is always an error. I've gotten it a couple times between yellow and red.

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According to the link at your wiki the RGB LEDs are rated for 2 to 3.2 volts. Your instructions for connecting the LED indicate connecting the LED to 5 volts on the Arduino Nano. I'm not sure why the LEDs don't burn out rather quickly when powered with 5 volts. Maybe you are doing something in the sketch to limit the current. The LEDs apparently come with resistors which could be used to limit the current so the LEDs do not burn out, but these resistors are apparently not included in your kits.

The Arduino Nano has a 3.3 volt pin which could be used instead of the 5 volt pin. Using that pin might protect the LEDs, but using one of the resistors on the power leg of the LED might also be a good idea.


thanks, Chris, i haven't seen any LEDs burn out yet, and we've been running them for weeks in some cases. If they do, i'll definitely add in a resistor. Thanks!

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