BQ34Z100-G1 OCVTAKEN bit won't toggle

Chekov Castillo33

Other Parts Discussed in Thread: BQ34Z100-G1, GPCRA0, BQ34Z100EVM, GPCCHEM

Hi,

I am having trouble making the BQ34Z100-G1 to work. I followed the procedure for the optimization cycles I found online (forums, TI datasheets, etc) but the OCVTAKEN bit just won't toggle. I have tried charging from full discharge and let the battery pack rest for almost 24 hours but the OCVTAKEN did not toggle. I also tried doing the reverse, from full charge to full discharge using a discharge rate greater than C/10 and then let the pack rest for hours but still no change (OCVTAKEN bit still low). What am I doing wrong?

My setup:

Three(3) 12V 55Ah Lead Acid batteries connected in series - 36V nominal pack

Attaching GG file and image of battery studio. Thanks!

PbA Pack.gg.rar

over 9 years ago

0 ThomasCosby over 9 years ago

TI__Guru 73830 points

I reviewed you gg file and here are a few comments.

The Quit Current needs to be set lower than the CHG and DSG Current Thresholds.
The Max Qmax Change should be set to 100
The Max Res Scale should be set to 32000
The Min Res Scale should be set to 1
The Faslh Update OK Cell Voltage should be set to 1000

If you have a log file for the discharge, then I can review it and may find other concerns.

0 Chekov Castillo33 over 9 years ago in reply to ThomasCosby

Prodigy 20 points

Thanks! It's working now.

0 Buyssens Hubert over 8 years ago in reply to ThomasCosby

Intellectual 685 points

Hi Tom,

I've tried to run learning cycle with chemID 457, that you send me by email on tuesday.

But I have the same problem : OCVTAKEN won't set and update status stay at 04, after more than 12H...

I've checked the comment from your last post, all is good, except the OK cell voltage = 2800, because I'm using just one cell in series (LiFEPO4).

Do you have an explanation ? (log in attachment )170419_04 - BMS1_V1-4 - learning cycle RST_ITen.zip

0 ThomasCosby over 8 years ago in reply to Buyssens Hubert

TI__Guru 73830 points

It looks like the Flash Update OK Voltage is probably the problem. The log file shows that Qmax should have updated, but this was prevented, because the cell voltage was below 2800mV. You should be able to use log data and submit it to the GPCRA0 tool and find Qmax and the Ra table data without having to rerun the cycle.

0 Buyssens Hubert over 8 years ago in reply to ThomasCosby

Intellectual 685 points

If possible, I preferred to understand how to run an entire learning cycle.

It seem to be OK for the chemID now, and I'd like to make a good golden image for testing on other prototype.

If I understand, I have to end the discharge before getting under 2800mV, or lower the voltage that prevent writing under 2700mV if I want to end the discharge at 2700mV?

Regards,

0 ThomasCosby over 8 years ago in reply to Buyssens Hubert

TI__Guru 73830 points

Here is a link where provide the steps to running the optimization cycle.

e2e.ti.com/.../1774822

0 Kornel Straub over 8 years ago in reply to ThomasCosby

Prodigy 170 points

Hello,

I have similar issue. I'd like to use bq34z100EVM board with a lead acid pack of 6 series cells. At the moment it is a Panasonic LP-R127R2.
I've done the configuration, the calibration, EnableIT, and charging to full. (I've attached my config and log.)
The charging current dropped to a few mAs, the TrueRC got to 7464 mAh and FC is set in Flags. The VOK and QEN is set int eh Control Status.

Even after 4 hours of relaxing the OCVTAKEN hasn't been set. When I've started the discharge with C/10 to TrueRC jumped to 0 immediately.

Unfortunately, I couldn't save the log with BatteryManagementStudio, because it rfused creating both config and log files. After restart of BatteryManagementStudio I saved the config and attached.

Thanks,

KornelEVM_03_Pana_LC-R127R2PG_04.gg.zip

0 Onyx Ahiakwo over 8 years ago in reply to Kornel Straub

TI__Guru* 76230 points

Did you identify the chem id for that LP-R127R2 using our gpcchem tool and did you program the chem id before starting your learning cycle?

thanks
Onyx

0 Kornel Straub over 8 years ago in reply to Onyx Ahiakwo

Prodigy 170 points

Hello,

I'd like to kill two birds with one stone: do the logging for the chemistry identification and do some testing. The chemistry was set to 808, which looks a similar cell.

I thought, the OCVTAKEN shall be set if the pack is relaxed at near the charge/termination voltage and the dV/dt condition is met.

Ok, now I run a logging of chg/dchg cycle for chemistry matching then I retry.

Thanks,
Kornel

Power management

Power management forum

BQ34Z100-G1 OCVTAKEN bit won't toggle