Practical starting point from Rcal Ohm measurement:

* RCal (Ohm), wbo2 calibration starting value (and absolute minimum value)

* 30 0 (0)

* 50 62 (60)

* 70 105 (102)

* 90 149 (133)

* 100 164 (145)

* 110 179 (157) (slope in this range is appr. +1/ Ohm )

* 120 186 (167)

* 130 193 (176)

* 200 228 (220)

* 300 255 (252)

These are decimal values. These are speculation, not measurement.

Some stats from actualy calibration - show that higher calibration value is needed than the above table suggests

* Rcal=113 Ohm, wbo2_calibration=BC (188) Karkus Audi

* wbo2_calibration=B8 (184) MembersPage/MarcellGal/EngineSwap TODO: measure RCal, IIRC 116 Ohm

* for Rcal=129 Ohm, wbo2_calibration=BD (189) MembersPage/GolfGtiLpg

* wbo2_calibration=CB (203) MembersPage/MarcellGal/PowerAndTraction TODO: measure RCal, IIRC 135 Ohm

* ... add more measurement / calibration !

Free air calibration

The calibration parameter above should be fine tuned in free air without the sensor installed. In free air the LCD(or terminal Manmde02mll)O2% should read 2095 which is 20.95%. After the sensor is warmed up you can adjust the wbo2_calibration parameter up or down to increase or decrease the reading being displayed. For a sanity check it is good to let the sensor cool down and warm back up to make sure the reading is still at 2095.

Breath Test

After configuring the above free air reading, you can breath on the sensor and see the 02% go down 100-200 counts(1-2%) to varify that all is working well

earlier notes before the values were tuned:

Ip measured 3.4 mA (and it lowered immediately when I exhaled on the sensor, it went back relatively slowly). That calculated to Rcal=147. I pulled apart the connector, and measured what Bosch applied. RCal was 149 Ohm. Fair enough.

Below the PID values are very bad, some 10 lines should be applied to wbo2log.pl to write Ri,DC, the integrals and the command-values to a file, and call gnuplot to plot against time.

WBO2 Config.

Make the PID better, but still works:

<code>

wbo2_warmup_ramp=0xA0 # 0.2 V/sec wbo2, warmup ramp speed [1.51 mV/sec]

wbo2_warmup_target=0xFF # variable dropped a long ago

wbo2_abs_limit=0xE4 # wbo2, heater absolute limit [?] (DA)

wbo2_limit_maxt=0xA0 # wbo2, max time spent at abs_limit [262msec] (50)

wbo2_fallback=0xB0 # wbo2, fallback V after maxt (0xC0 will heat it better than 0x60, especially when 350C exhaust gas cools the 750C sensor element at idle)

wbo2_retry_t=0x06 # wbo2, retry control after [4sec]

wbo2_edgetime_corr=0xBA # variable dropped in most recent firmwares

wbo2_edgetime_min=0x50 # variable dropped in most recent firmwares

wbo2_ri_target=0x96 #wbo2, target Ri (pulse amplitude) [5V/8192]

wbo2_nernstdc_target=0x89 # controller specific (controller not sensitive to very precise setting), usually 0x89 gives most precise 0.45V between nernst and pump-

wbo2_pump_pw_zero=0x65 ## controller specific. Look up webshop mail (or calibrate for your controller for minimum pump current absolute value: pump+ closest to pump- at startup)

wbo2_calibration=0xD0 ## Calibrate yourself for sensor!

wbo2_heater_pid_kp=0x46

wbo2_heater_pid_ki=0x10

wbo2_heater_pid_kd=0x1A

wbo2_heater_pid_ilimit=0x80

wbo2_pump_pid_kp=15

wbo2_pump_pid_ki=4E

wbo2_pump_pid_kd=00

wbo2_pump_pid_ilimit=0x84

wbo2_ri_confidence_scale=0x80

</code>