mistermike
June 19th, 2007, 03:54 AM
I finally decided to replace the Fluke 87 that was stolen from my job so I could calibrate the widebands to my V2 cable. Nothing quite like 50,000 count accuracy and automation up the yingyang.
http://www.tecratools.com/pages/service/graphics/37289l.jpg
Interestingly, I didn't have much luck using the recommended procedure for tweaking the V2 A/D calibration, particularly in light of the D/A output error in the LC-1, and used an alternative technique. I set low side to 0V and told the high side it was seeing the commanded voltage rather than the actual. FWIW, my AFR's using the standard PID now track the LogWorks value within less than 0.2 AFR error over the range of interest. It would appear that there's more than one way to skin that cat. Although I didn't go this way, I'm going to try to come up with a spreadsheet that will allow you to do your calibration on the LC-1 side, but it will be a little tricky and will require an accurate meter.
http://www.tecratools.com/pages/service/graphics/37289l.jpg
Interestingly, I didn't have much luck using the recommended procedure for tweaking the V2 A/D calibration, particularly in light of the D/A output error in the LC-1, and used an alternative technique. I set low side to 0V and told the high side it was seeing the commanded voltage rather than the actual. FWIW, my AFR's using the standard PID now track the LogWorks value within less than 0.2 AFR error over the range of interest. It would appear that there's more than one way to skin that cat. Although I didn't go this way, I'm going to try to come up with a spreadsheet that will allow you to do your calibration on the LC-1 side, but it will be a little tricky and will require an accurate meter.