WB02 - Input to MJ to retard timing on lean condition
Moderators: JeffC, rdoherty, stieg, brentp
WB02 - Input to MJ to retard timing on lean condition
Has anyone figured out how to take the output from a Wide Band 02 and use it with MJ? I was thinking that it would be interesting to be able to have the mj retard the timing if it saw a af reading of say 13.9 or higher. This would help prevent detonation or a lean burn condition (possibly saving a motor.)
Respectfully
Dean
Dean
This would be a great use of the AUX input.
You would need to calibrate the Aux input, scaling the measured 0-5v input to a value between 0 - 255 that is meaningful to your application.
The default calibration has 0 volts = 0 and 5v=255, linearly scaled.
After performing any calibration you need, you would set the advance correction table as necessary.
Review the Operation guide for more details on this topic, and let us know when you have it set up on your engine!
Regards,
You would need to calibrate the Aux input, scaling the measured 0-5v input to a value between 0 - 255 that is meaningful to your application.
The default calibration has 0 volts = 0 and 5v=255, linearly scaled.
After performing any calibration you need, you would set the advance correction table as necessary.
Review the Operation guide for more details on this topic, and let us know when you have it set up on your engine!
Regards,
Brent,
Thanks!!!!!! That is exactly what I was looking for I will read up on that and more than likely have more questions!!!!
I am using a JAW unit. It has a lot of flexibility for this king of thing. I think I will contact Alan and let him know about another use for his product. BTW the JAW is definitely not for everyone but it is a great alternative to many of the other ones that are out there. Basically if you are like me and don't like throwing $$$$ at things and are willing to invest a bit of time (Like the MJ) the JAW is a great alternative. I have had my JAW nit up and running for the better part of a year. I have moved it from several cars (race cars) and it has performed flawlesly. I am really excited about melding it to the MJ and making the two of them "work together". To me it is a win win. It makes both units better. It is like adding one and one and getting three!! I can not wait to get this up and running.
Thanks!!!!!! That is exactly what I was looking for I will read up on that and more than likely have more questions!!!!
I am using a JAW unit. It has a lot of flexibility for this king of thing. I think I will contact Alan and let him know about another use for his product. BTW the JAW is definitely not for everyone but it is a great alternative to many of the other ones that are out there. Basically if you are like me and don't like throwing $$$$ at things and are willing to invest a bit of time (Like the MJ) the JAW is a great alternative. I have had my JAW nit up and running for the better part of a year. I have moved it from several cars (race cars) and it has performed flawlesly. I am really excited about melding it to the MJ and making the two of them "work together". To me it is a win win. It makes both units better. It is like adding one and one and getting three!! I can not wait to get this up and running.
Respectfully
Dean
Dean
Brent,
I need some help with this. Looking at the aux setup I have run in to some snags. I can make this work it is just not very pretty and more importantly it is not all the intuitive to he end user.
The problem as I see it:
You need to have 5 places in the scaled value volume 4 numerical and one for the decimal place. the would allow for the use of AFR numbers.
Solution #1: This really does not work well. It is to just put in the value with out the decimal IE 14.7 becomes 147. This kind of works BUT it still does not give me the fourth numerical place. I guess we can just accept that the WBO2 will have higher resolution. I am sure that it will work. It just bothers me that we can not have it more accurate. (For tuning purposes it probably does not matter)
The point being is that most WBO2's go to 4 numerical digits. When tuning it is that important and many tuners are tuning to that level of AFR
IE there is a difference between 12.5 and 12.59 when tuning.
The plus to this solution:
It is kind of in AFR format that the vast majority of people would understand.
The minus:
You have to interpret the decimal
You don't get 4 digit resolution
Solution #2:
Use lambda not AFR. It is a three digit number so you don't loose resolution However you will have to drop the decimal and most people don't know what it means. Most are use to tuning with AFR.
The lambda range on on my unit is:
.69 = 10.8 AFR at an output voltage of 2.06
2.33 = 34.28 AFR at an output voltage of 4.46
The plus to this solution:
You maintain the resolution of the WBO2 unit across to the MJ unit.
The minus:
You have to interpret the decimal
You are using a scale that most will not understand (not user friendly)
I have attached screen shots from my WBO2 so you can see the variables I have to work with. Note that I can slide the scale and change the # of vols per AFR for Bout #2 (where I will get the signal form the WBO2 for the MJ)
I have also attached a Excel file that may help you understand what I am doing (or trying to do)
Another question. Do I have to use all of the ADC scale (0-255) in the aux set up? In other words if I set the output from the WBO2 so that my max AFR reading of 34.28 (2.33 lambda or 233 on the scaled value table) is at 5 volts I then put the AFR of 14.7 (ideal AFR reading some say) at 2.51 volts (it should be 2.50 but because the aux does not have a 2.50V choice) and I scale the volts by .127 volts per AFR it puts my max reading at exactly 5 volts at 255 when I put it in to the AUX scaled value with very little collection. The problem is that my minimum ADC Value will be 99 as that is the lowest that my unit will read to with a voltage of 1.94 and a lambda reading of .69 (69 in the Scaled Value table) This correlates to a AFR reading of 10.18. Everything in the Scaled Value volume of the AUX table below 99 in the ADC column will be set to 0. I could enter values for this but the WBO2 does not go there so I don't thing it is needed it would just put back a 0 reading on the scale if WBO2 voltage output drops below the scale. this would let me know if there was an error in the output as well instead of giving me fictitious readings it would just put out 0.
Anyway this is way more than you probably want to look at but maybe others can look it over as well and see that they think.
I need some help with this. Looking at the aux setup I have run in to some snags. I can make this work it is just not very pretty and more importantly it is not all the intuitive to he end user.
The problem as I see it:
You need to have 5 places in the scaled value volume 4 numerical and one for the decimal place. the would allow for the use of AFR numbers.
Solution #1: This really does not work well. It is to just put in the value with out the decimal IE 14.7 becomes 147. This kind of works BUT it still does not give me the fourth numerical place. I guess we can just accept that the WBO2 will have higher resolution. I am sure that it will work. It just bothers me that we can not have it more accurate. (For tuning purposes it probably does not matter)
The point being is that most WBO2's go to 4 numerical digits. When tuning it is that important and many tuners are tuning to that level of AFR
IE there is a difference between 12.5 and 12.59 when tuning.
The plus to this solution:
It is kind of in AFR format that the vast majority of people would understand.
The minus:
You have to interpret the decimal
You don't get 4 digit resolution
Solution #2:
Use lambda not AFR. It is a three digit number so you don't loose resolution However you will have to drop the decimal and most people don't know what it means. Most are use to tuning with AFR.
The lambda range on on my unit is:
.69 = 10.8 AFR at an output voltage of 2.06
2.33 = 34.28 AFR at an output voltage of 4.46
The plus to this solution:
You maintain the resolution of the WBO2 unit across to the MJ unit.
The minus:
You have to interpret the decimal
You are using a scale that most will not understand (not user friendly)
I have attached screen shots from my WBO2 so you can see the variables I have to work with. Note that I can slide the scale and change the # of vols per AFR for Bout #2 (where I will get the signal form the WBO2 for the MJ)
I have also attached a Excel file that may help you understand what I am doing (or trying to do)
Another question. Do I have to use all of the ADC scale (0-255) in the aux set up? In other words if I set the output from the WBO2 so that my max AFR reading of 34.28 (2.33 lambda or 233 on the scaled value table) is at 5 volts I then put the AFR of 14.7 (ideal AFR reading some say) at 2.51 volts (it should be 2.50 but because the aux does not have a 2.50V choice) and I scale the volts by .127 volts per AFR it puts my max reading at exactly 5 volts at 255 when I put it in to the AUX scaled value with very little collection. The problem is that my minimum ADC Value will be 99 as that is the lowest that my unit will read to with a voltage of 1.94 and a lambda reading of .69 (69 in the Scaled Value table) This correlates to a AFR reading of 10.18. Everything in the Scaled Value volume of the AUX table below 99 in the ADC column will be set to 0. I could enter values for this but the WBO2 does not go there so I don't thing it is needed it would just put back a 0 reading on the scale if WBO2 voltage output drops below the scale. this would let me know if there was an error in the output as well instead of giving me fictitious readings it would just put out 0.
Anyway this is way more than you probably want to look at but maybe others can look it over as well and see that they think.
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- WBO2-low.jpg (163.63 KiB) Viewed 4748 times
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- WBO2-high.jpg (163.85 KiB) Viewed 4748 times
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- wbo2.xls
- (53 KiB) Downloaded 547 times
Respectfully
Dean
Dean
Hi Dean,
The AUX input is an 8 bit value, so that limits you to 0-255. Currently, the software only allows scaling in whole numbers, but I'm looking at fractional scaling to make these scenarios more usable. Agreed that for tuning purposes 1 decimal place would typically work well enough.
The Aux calibration allows you to translate a raw measured value to any 8 bit value you wish, so you can indeed set a narrow window with zeros padded at the ends.
The AUX input is an 8 bit value, so that limits you to 0-255. Currently, the software only allows scaling in whole numbers, but I'm looking at fractional scaling to make these scenarios more usable. Agreed that for tuning purposes 1 decimal place would typically work well enough.
The Aux calibration allows you to translate a raw measured value to any 8 bit value you wish, so you can indeed set a narrow window with zeros padded at the ends.