100a daly BMS not giving 100a

[Tasemu]

Hi all. I have my lifepo4 setup working for a few months now but i've noticed that if I draw more than 70 amps from my 100a model, it cuts out for over current. I have a 2s daly smart bms 100a. Is this common with daly or could it just be my unit?

Thanks in advance!

 

[MisterSandals]

I have a 2s daly smart bms 100a.

So what battery has 2 cells? Or who makes a 2S BMS?
A LiFePO4 should be 3.2v per cell.

 

[Tasemu]

So what battery has 2 cells? Or who makes a 2S BMS?
A LiFePO4 should be 3.2v per cell.

Apologies, typo there, I meant 12v 4s.

 

[MisterSandals]

if I draw more than 70 amps from my 100a model, it cuts out for over current.

Sounds like a faulty unit. Do you have any recourse from where you bought it?

 

[Zwy]

Hi all. I have my lifepo4 setup working for a few months now but i've noticed that if I draw more than 70 amps from my 100a model, it cuts out for over current. I have a 2s daly smart bms 100a. Is this common with daly or could it just be my unit?

Thanks in advance!

When it happens, what do your cells read for voltage? Did you top balance the cells?

Daly should really be derated by at least 30%. I purchased a 250A model for a max expected load under 150A.

 

[OTRwSolar]

It's possible your Daly needs to have the current calibrated (using Sinowealth). If it's off all the current set points will be inaccurate. I've seen the calibration so far off that it shows charge current as discharge current. When it's this far off the BMS will use the charge mosfets for discharge functions and vice versa. You'll see the CADC Gain change to reflect the differential as you calibrate. You can calibrate using either charge or discharge current. Be sure to use the proper polarity (charge pos/discharge neg) when you make your entries. I use a small bench-top regulated power supply to calibrate my Daly. Current readings on my unit are accurate to within 100mv in the 0-1a range. Around 100-150a, it's within 1-2%.

 

[Tasemu]

When it happens, what do your cells read for voltage? Did you top balance the cells?

Daly should really be derated by at least 30%. I purchased a 250A model for a max expected load under 150A.

That makes sense if mine cuts out at about 20-30% short. Guess I gotta upgrade.

 

[HighTechLab]

It's possible your Daly needs to have the current calibrated (using Sinowealth). If it's off all the current set points will be inaccurate. I've seen the calibration so far off that it shows charge current as discharge current. When it's this far off the BMS will use the charge mosfets for discharge functions and vice versa. You'll see the CADC Gain change to reflect the differential as you calibrate. You can calibrate using either charge or discharge current. Be sure to use the proper polarity (charge pos/discharge neg) when you make your entries. I use a small bench-top regulated power supply to calibrate my Daly. Current readings on my unit are accurate to within 100mv in the 0-1a range. Around 100-150a, it's within 1-2%.

Beat me to it ?. I should make a video on how to do this.

 

[JimJr]

Check you cell voltage while on a draw at 70-100 amp

 

[Nivya]

Hi, I have a current calibration problem with my Daly BMS. It is off by a few amps which is problem in case of over current protection. I have PCMaster installed in my PC. But it shows an error (a red mark) whenever I try to do the 10A calibration test. The current accuracy test does not work as well. Any ideas about how to calibrate it the right way?

 

[chladekj]

Did you solve the problem? In the lower-left corner, there is an error "EEPROM storage fault"

View attachment 115784

 

[chladekj]

Hi, I have a current calibration problem with my Daly BMS. It is off by a few amps which is problem in case of over current protection. I have PCMaster installed in my PC. But it shows an error (a red mark) whenever I try to do the 10A calibration test. The current accuracy test does not work as well. Any ideas about how to calibrate it the right way?

Did you solve the problem? In the lower-left corner, there is an error "EEPROM storage fault"