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Wideband Lambda Sensor
82 Locost - 11/6/08 at 03:55 PM

Quick question.

If I wire a wideband lambda sensor up can I just read the output voltage or do I need some kind of hardware to convert the output to a voltage? I'm assuming the sensor just measures AFR, and that measurement translates into a voltage which can be measured with a voltmeter.

Presumably, there's also a voltage output which translates to the 'ideal' AFR?

Agriv8 - 11/6/08 at 03:57 PM

I know on my vems system there is a calibration setup to go through when ever you introduce a new Wideband sensor.

HTH

Regards

Agriv8

BenB - 11/6/08 at 04:00 PM

Normally the wideband controller corrects for temperature etc and then either outputs a given voltage or serial connection etc etc.

If you tried to measure the resistance of a wideband sensor you won't get much usable information.

But you can just attach a wideband controller and measure the volts coming out of it to get the wideband lamba reading (typically 14.1 ratio gives 1.41volts etc etc). It's only if you want a flash dial or to view the result on a laptop (for datalogging purposes etc) that you need the dials etc.

pajsh - 11/6/08 at 04:01 PM

Why not ask Omega0684.

Clicky Here

82 Locost - 11/6/08 at 04:51 PM

BenB and Robocog seem to be in slight disagreement.

I'm hoping to link to output to a data logger to record how lambda changes with revs under different loads to get a set of graphs.

If Ben's right then I'm happy. If Robocog's right then my plan is b@ggered.

rachaeljf - 11/6/08 at 05:05 PM

No they're not. You have to have a controller to manage the Nernst cell in the wideband sensor. The controller then outputs a helpful linear voltage that represents the a/f ratio. You will get nothing useful out of a wideband sensor without its controller I'm afraid.

stevebubs - 11/6/08 at 05:41 PM

quote:
Originally posted by rachaeljf
No they're not. You have to have a controller to manage the Nernst cell in the wideband sensor. The controller then outputs a helpful linear voltage that represents the a/f ratio. You will get nothing useful out of a wideband sensor without its controller I'm afraid.


Ditto

MikeRJ - 11/6/08 at 06:15 PM

quote:
Originally posted by 82 Locost
BenB and Robocog seem to be in slight disagreement.

I'm hoping to link to output to a data logger to record how lambda changes with revs under different loads to get a set of graphs.

If Ben's right then I'm happy. If Robocog's right then my plan is b@ggered.


That depends! When you say "wideband lambda sensor", do you simply mean the sensor itself, or a complete setup with a wideband controller such as the JAW or Innovate LC-1?

If the former, then no since a wideband lambda does not produce a voltage output like the narrow band ones.

If the latter then yes, since the controllers can generally be configured to output the voltage and slope you require. 0.1v = 0.1 lambda is a very common output.

82 Locost - 11/6/08 at 09:13 PM

Thanks guys. I guess the answer is that I can't use a data logger to plot graphs of lambda vs rpm unless I spend money on a controller.

Thanks for the help.

adithorp - 14/6/08 at 06:05 PM

Have you seen this thread?

http://www.locostbuilders.co.uk/viewthread.php?tid=89241

adrian