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DISCUSSION => Electrical => Topic started by: mrjezza on June 20, 2006, 07:29:47 PM

Title: Closed Loop Monitor
Post by: mrjezza on June 20, 2006, 07:29:47 PM

http://autospeed.drive.com.au/cms/A_1716/article.html

Does anyone know how one of these works (read: how I can make  one without subscribing to that website ;))?

Title: Closed Loop Monitor
Post by: johna on June 20, 2006, 07:49:59 PM

If you click the Print Article link (http://autospeed.drive.com.au/cms/A_1716/printArticle.html (http://autospeed.drive.com.au/cms/A_1716/printArticle.html)) you get some small photos from which you can probably work out the wiring.

Title: Closed Loop Monitor
Post by: johna on June 20, 2006, 08:48:10 PM

...and the photos are pretty easy to access too if you know what to look for:

Title: Closed Loop Monitor
Post by: mrjezza on June 21, 2006, 02:06:09 AM

Legend :)  I initially tried to access the pages by typing in page names manually but that didn't work so it never occurred to me it would for the images.

Well done ;)

Title: Closed Loop Monitor
Post by: bmwman91 on June 21, 2006, 11:41:19 AM

So....it looks to see if the O2 output keeps bouncing above & below .45V (closed loop) vs. going consistently higher (richer at WOT & open-loop)?

The LM311 is a voltage comparator...and I guess the pot sets the O2 output threshold at which the LED gets turned on?  Pretty nifty simple little device.  For under $10 I would say it is worth it for tinkering enjoyment.