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I would like to build an AFR meter using an Arduino board, and I would like to know if anyone has a detailed chart of voltage v AFR for a narrow-band oxygen sensor. 

Yes, I searched for a  long while, but you guys usually have useful engine data.  There are lots of chart images, but they all look like a curvey Z, so obviously, there isn't enough detail to pick out coordinates to plot in a spreadsheet.

If I had a chart or table with enough detail, I could generate a formula  or a lookup table.  The former would be better.

It's just too bad the LCD displays are monochrome, because colour would be easier to interpret while driving,  I suppose I could add some colored or RGB LEDs.

thxZ

 

Chart 2.gif

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Thanks, but that guy's data doesn't make sense, and he says it's not correct, especially for lambda=1. He gives 0.33V  for lambda=1.0 but it should be about .45V . Then says he used a wide-band controller to get measurements from a narrow-band sensor?   He also needs to change the way he explains the theory of the sensor, as he says the fuel "pulls oxygen through"  for both rich and lean conditions.

That's why I passed this page the first time I viewed it.

Edited by TomoHawk

15 hours ago, TomoHawk said:

Yes, I searched for a  long while, but you guys usually have useful engine data.  There are lots of chart images, but they all look like a curvey Z, so obviously, there isn't enough detail to pick out coordinates to plot in a spreadsheet.

You'll have to measure temperature also, as shown in your plot, even with a lookup table.

Why use a narrow band when wide bands are available?

Narrow band is very limited in application.  Wide band gives you what you said you wanted.  Unless you're really trying to "outdo" the engineers that didn't make narrow band sensors work for AFR measurement.  Or you aren't looking for accuracy.  Good luck.

https://en.wikipedia.org/wiki/Oxygen_sensor#Wideband_zirconia_sensor

http://www.walkerproducts.com/o2-sensor-training-guide/history/

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17 hours ago, TomoHawk said:

I would like to build an AFR meter using an Arduino board, and I would like to know if anyone has a detailed chart of voltage v AFR for a narrow-band oxygen sensor

You said you wanted narrow band...?

Just trying to help.  Good luck.

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