MembersPage/DuncanThomson (2006-01-31 07:18:08)

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Project Description

Looking to install a v3.2 Genboard onto a naturally aspirated Audi inline 5 cylinder engine (KV).


Questions

WB02 calibration

Following the procedure for calibration, and the voltage checks for the pins are giving me trouble. Docs specify 3.96v from GND to Pump -ve, and 4.41 from GND to Nernst, with 450mv from -ve to nernst.

Following are the measurements I have been getting. Is there any way to get the pump -ve down to 3.96 volts? Also looking for a little more feedback on the PID settings. What sort of time constant are we modelling for, and is there any other info that might be useful for tuning the PID loop?

{{pump testing

wbo2_nernstdc_target 134 160 160 160

wbo2_pump_pid_kp 64 64 64 64

wbo2_pump_pid_ki 44 44 44 124

wbo2_pump_pid_kd 8 8 0 0

wbo2_pump_pid_ilimit 132 132 132 132

gnd - pump- V 4.06 4.03 4.03 4.05

gnd - nernst V 4.3 4.36 4.39 4.5

nernst - pump- mV -240 -330 -360 -450

}}


Answered Questions

Crank sensor

I'm looking at using a VR sensor to pick up on a 60-2 toothed wheel which will be attached to the crank pulley.

If you have a space EC36 pin, it might be a good investment to have a separate pin for VR- that is connected to GND near the LM1815 chip (not through the EC36-pin26 GND). The idea is to keep signal seen by LM1815 very clean for best lowRPM (<200 RPM , small signal) behaviour. Although EC36pin26 GND is not as noisy (by far) as the GND5 decreasing it further might be a good investment if the free EC.. pin is available and ECM unassembled. EC.. is perfect, just sharing current paths might (which is common for GND) inject some noise (that is usually below problematic limits).

At this stage it looks like I'll need a number of extra connections through the endplate, so far:

Looks like it may be necessary to mount a number of these on the rear endplate with long cables so I can remove the board from the case if necessary.

MAP Sensor

I recommend mounting MAP on the top of the board. Better for getting the tube through the frontplate. Note that MPX4250AP pins must be bent to the other direction depending on the top/bottom (so that notched pin is close to AVR in any case)


Progress