Alternator duty not following commanded voltage Tune/logs

[nathaninwa]

Was able to get the car fired up today after some fuel cell work. From my other thread I was able to get alternator control to work with the GM two wire setup for about 15 seconds before I tore into the cell

Today getting it fired up, I brought up alt-duty, target voltage and battery voltage to fine tune the duty cycle

On initial start up its commanded to run 15V and alt-duty followed the open loop table and I got it dialed in Let it run through its charge cylcle and voltage dropped along with target and alt-duty

I then key cycled and restarted and target voltage went back to 15 but battery volts was low and I noticed the alt-duty was low, long story shortened up, the code seems to be stuck at the 14.5 voltage duty, I can vary the 14.5 duty row and get it follow, but when target is at 15, the duty stays low

1.4.1 beta 1

[nathaninwa]

Let the car sit for about 30 mins while I changed out wastegates. Fired it back to check for leaks and it seems it's not responding to the short duration charge mode, but starts up in run mode

[jsmcortina]

I don't think your alternator duties are correct. I tested a number of alternators on the bench late last year.

Target Voltage Duty
11.0V 10%
11.8V 26%
12.8V 42%
13.7V 58%
14.6V 74%
15.5V 90%

James

[nathaninwa]

I tried the default like you posted. Voltage was low. I thought it was from the 1k pull-up I used. I installed a 470ohm resistor and the results didn't change.

What's strange is the initial fire up the duty followed my 15volt target and I could adjust. After that it seems to be stuck at the run 14.5 voltage point, duty cycle commanded. At first it was stuck at 81% but while it's in charge mode, it should be commanding like 90%, I can adjust the duty by changing the 14.5 volt row. I'm happy that it's charging, and have futzed the 14.5 row to get me 14.7 with fan off and 14.5 with fan on

Still need to get it out and run it with the hood closed to see how heat may affect voltage output

[nathaninwa]

Heres some logs and the corrected tune

Charge voltage is 15 volts but the DC is stuck at the 74% 14.6 run mode Voltage is low at 14.3, measure at the battery and at TS

second log is the ramp down voltage from 15 to 14.6 and DC stays constant at 74%

I then changed run voltage to 15v during the log and nothing changed to the DC I was able to change the DC percent at the run voltage to 90% and TS made the change and voltage went up to 14.9

[jsmcortina]

Please upgrade to the current release firmware. A number of tweaks were made to alternator last year that you are missing out on.

James

[nathaninwa]

Upgraded firmware and all seems to be working as it should