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Daly BMS app stays at 100% on low amp discharge

camdee

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Dec 14, 2020
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Hi everyone,

I got a 100ah 12v Lifepo4 prismatic cell pack on a Daly 100A BMS with bluetooth.

I have set the DalyBMS sleep setting to 15300 so it doesnt fall asleep and I can check whenever I want the state of the pack.

In the last few days, I have put my CPAP with a 12v adapter on this battery pack to test it in off the settings.

After two 7 hours night of sleep, the Bluetooth app still says my battery is at 100% of soc.

When the CPAP runs at low setting, it doesnt draw much in terms of AMP. Below 2 amps for sure, maybe 1 amp. The Daly/app doesnt seem to detect that such current is being drawn. So I think the Daly BMS is not sensitive enough to detect under 2 amps current. Thus the app stays at 100% all the time.

Am I right in my thinking ? any settings I should look into ?
 
Mine is also doing this
 

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If you have access to the UART to USB cable for programming it is possible to alter the 2000mA standard setting down to 500mA. There is a slight "hunting" effect that seems to occur which will vary from 100mA-420mA (based on my testing) so although it is possible to get the sensing all the way down to 50-100mA, the screen will constantly indicate a (-) to (+) alternating current draw even with no connection to the battery or loads.
500mA is the sweet spot :)
 
I have the same Daly 4S 12V 100A bms and am also not able to show amps below 2000 mA.

Above 2 amps the current displays correct!

@CampCreekRV. Can you explain more about the 2000 mA standard setting? How to alter?
And yes, i do have the UART/PC cable and the Sinowealth program.
 
I have two 12V 4S 200A Smart BMS. I am assuming that the 100 may have the same programming features as per the 200 & 250A versions.
You are looking for the "Dfilter" setting which has a standard 2000mA set point.
Simply set the filter current to 500mA.
The setting is in the top tight area of this image, you will notice it is set at 100mA during my testing but 500mA us the lowest practical set point.
20210318_154251.jpg
 
Hi everyone,

I got a 100ah 12v Lifepo4 prismatic cell pack on a Daly 100A BMS with bluetooth.

I have set the DalyBMS sleep setting to 15300 so it doesnt fall asleep and I can check whenever I want the state of the pack.

In the last few days, I have put my CPAP with a 12v adapter on this battery pack to test it in off the settings.

After two 7 hours night of sleep, the Bluetooth app still says my battery is at 100% of soc.

When the CPAP runs at low setting, it doesnt draw much in terms of AMP. Below 2 amps for sure, maybe 1 amp. The Daly/app doesnt seem to detect that such current is being drawn. So I think the Daly BMS is not sensitive enough to detect under 2 amps current. Thus the app stays at 100% all the time.

Am I right in my thinking ? any settings I should look into ?
Did you reset zero calibration with no load on the system? It's on the last page of the bluetooth app. I did mine at full charge and no load. Works just fine.
 
@CampCreekRV. Thanks a lot!!!

In the Sinowealth program the setting is in MCU System and there it is called DfitterCur. Probably chinese/english for DfilterCur.
Maybe short for Display Filter Current?

I made this DfitterCur "0". Then do a zero current calibration with no load connected. Next did a calibration with a 5 amp load.

When there is no load connected, the current display in the Sinowealth program shows the following values:
+/- 0, 8, 17, 26, 35, 43, 52, 61, 70 mA

So 9 mA seems to be the minimum ADC (Analog Digital Converter) resolution.

To avoid these jumping current values you can set the DfitterCur to 100 mA. Now you have a steady zero "0" current display when no load is connected. And as soon there is more then 100 mA load the current display shows some value. This value is not very accurate, it has a precision of +/- 70 mA or so.

Below 8 minute logging of 0 mA
Daly_DfitterCur.jpg

Altering the CADC Zero gives 140 mA change per unit. The zero current calibration is thereby limited to +/- 70 mA.
If i change CADC Zero value from 4 to 5, my average "0" mA goes from +27 mA to -113 mA.
Daly_CADC_Zero.jpg

I changed the default value 2000 mA to 75 mA in my bms. Now the SOC is updated with low amp discharge.
Although not accurate, always better than nothing.
Daly_DfitterCur_75.jpg
 
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Did you reset zero calibration with no load on the system? It's on the last page of the bluetooth app. I did mine at full charge and no load. Works just fine.
Does yours show loads below 2 amps? I can’t access the USB since mine is a sealed battery. I only have access to Bluetooth
 
Sorry to resurect this topic but I have the same issue and not sure what's the best value to set the DfitterCur to so I can see the draw corectly. I think I would be happy with 500mah but what I noticed atm without modifying anything the draw is not really accurate, I put the clamp meter on a 16A draw showed by the bms and the acutal draw was about 18.5A(on the clamp meter). And the most important question can I use any other USB-Uart cable than the Daly cause if I order a daly one I would wait 2 months to be delivered to UK( at least) thanks to Brexit!!
 
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