Modern Device Forum

Is there a way to convert the output of the AMBI sensor to lumens or lux?

Your hack works flawlessly. Thank you so much!

Hello,

My TMP421 sensor running on the JeeNode worked great until the temps dropped below freezing. All of a sudden, the math to determine the temperature doesn't work! Here's the part of the sketch that pulls the bytes representing the temperature out of the TMP421:

DeviceI2C temperature (1 ...

Okay I can definitely say the extra 100k resistor did the trick. Today was a sunny day like the last three. Instead of hitting max value by 8:30 am, the light level didn't hit its max value until around noon, and there were variations up and down throughout the day as clouds went by, etc. The "max ...

Excellent feedback. Thank you. I'll experiment with it with a potentiometer over the next few days and let you know. I'm in Ohio so I should have similar sunshine to you. I'll let you know the results of my testing.

I have it plugged directly into the A, + and G pins on a JeeNode port, and I'm doing a straight Ports library anaRead() to get the value. So you're saying put another 100K between which pins? V0 and +5?

Well I may have found the answer to my own question. The maximum value this sensor can detect is 55000 lux. According to Wikipedia, direct sunlight can have a range of 32,000 to 120,000 lux. In my particular application, the sensor is in a Hoop House, similar to a very small greenhouse, in my garden ...

The markings on the sensor pointed me in the right direction. It's working like a champ!

I bought a couple of the AMBI light sensors and have one hooked up to log some outdoor brightness values. Looking at the data though, by 8:30am it got up to 996 and has stayed there since then. Has anyone seen theirs go past 996? I guess I'm a little surprised that it would hit its max value so ...

Could someone please post information for connecting the TMP421 sensor breakout to a JeeNode v4? I need to know which of the two rows of 4 holes the headers solder into, and if I can plug that directly into one of the "ports" on the JeeNode, or if I have to swap some pin positions.
Thanks!