Daly Smart BMS stops charging randomly

[John Frum]

We need to see the alarm log.

 

[Ampster]

I agree with @gnomie, the BMS is doing what it is supposed to do. Focus on the inverter charger as the potential problem. Also clarify when you state voltages whether those are settings, or measurements, and from what source are those measurements including if one of those is a voltmeter.

 

[Freeman656]

You mean in the GX ? There is nothing recent, the two notifications where from the installation, and on the BMS, nothing (as per screenshots)

 

[Freeman656]

Also clarify when you state voltages whether those are settings, or measurements, and from what source are those measurements including if one of those is a voltmeter.

Ok, all measurement are based on the smartshunt and the VRM graphs.
Settings are 56.8 and 54.0 in VE config for absorb and float.
And I found nowhere a configuration for maximum bulk voltage (only in DVCC which is not active in my case).

 

[John Frum]

You mean in the GX ? There is nothing recent, the two notifications where from the installation, and on the BMS, nothing (as per screenshots)

View attachment 134805

Assuming you are responding to me.
We need to see the alarm logs on the BMS.
It should have the most insight into why it is tripping.

 

[Ampster]

That graph explains what is going on. When the BMS cuts out, current goes to zero and voltage goes to 58 which says to me it has to be a setting on the Inverter/charger that is too high. I presume the logs would show the same thing?

 

[Freeman656]

We need to see the alarm logs on the BMS.

I posted a screenshot (post #4) right after the BMS shutdown, and there is no alarm event logged.

It should have the most insight into why it is tripping.

A agree but I can't see anything on the BMS.

When the BMS cuts out, current goes to zero and voltage goes to 58 which says to me it has to be a setting on the Inverter/charger that is too high.

Yes, I've check all the configuration and I found nothing to configure the bulk max charge voltage. Maybe if any Victron expert can help, could be useful

 

[John Frum]

I posted a screenshot (post #4) right after the BMS shutdown, and there is no alarm event logged.

A agree but I can't see anything on the BMS.


Yes, I've check all the configuration and I found nothing to configure the bulk max charge voltage. Maybe if any Victron expert can help, could be useful

If the BMS is opening the charge path without logging anything its not a very useful BMS.

 

[John Frum]

Some of the BMS triggers are to constrained.

high cell trigger should be 3.65 volts
low cell trigger should 2.5 volts

low pack trigger should be 40 volts

 

[Freeman656]

Ok I'll change these parameters for the future. I guess high pack you mean 58.4V.

 

[John Frum]

Ok I'll change these parameters for the future. I guess high pack you mean 58.4V.

Yes.

 

[John Frum]

The BMS should not be used for charge termination.
We would expect the voltage to spike if the BMS charge path is opened while charging.

 

[Freeman656]

Yes I get it, only for battery protection !
The rest is handled by the charger

 

[Ampster]

Ok, all measurement are based on the smartshunt and the VRM graphs.

Are those the voltage measurements at the battery or at the inverter when the BMS has disconnected. I understand which device is giving you those measurments, I am asking at what point in the circuit are the measurements taken? Have you verified them with voltmeter?

 

[Freeman656]

It's taken by the smartshunt on the MP connectors.
At the battery level, I have no logging of data, I guess the BMS only displays realtime data.

I did not verify these measurement because it lasts for a few seconds, maybe less, so unless I use a ESP32 voltage logger or some sort of thing I'm not able to be right on time with a voltmeter. But I verified the voltage during the bulk/ absorb phases and it's correct.

 

[John Frum]

It's taken by the smartshunt on the MP connectors.
At the battery level, I have no logging of data, I guess the BMS only displays realtime data.

I did not verify these measurement because it lasts for a few seconds, maybe less, so unless I use a ESP32 voltage logger or some sort of thing I'm not able to be right on time with a voltmeter. But I verified the voltage during the bulk/ absorb phases and it's correct.

The BMS should be logging alarms.

 

[John Frum]

There is a section heading on the dashboard page.
"informations d'etat" which translates to "status information"
This is where the alarms should be logged.

 

[Freeman656]

Yep, empty !
But maybe the status is only displayed when there is an overvoltage, not after, because after a few seconds, the absorbtion voltage comes back to a normal state, so the information status on the BMS disappear, but the Chgr MOS stays off ?? Maybe it will get online again after a period of time after it tripped ?

 

[John Frum]

Yep, empty !
But maybe the status is only displayed when there is an overvoltage, not after, because after a few seconds, the absorbtion voltage comes back to a normal state, so the information status on the BMS disappear, but the Chgr MOS stays off ?? Maybe it will get online again after a period of time after it tripped ?

That would be fairly useless.
The alarm should at least persist until the status section has been seen(navigated to).
It might clear when the user navigates away from the page though.

 

[John Frum]

Hi again,
I've a charging issue with my Daly (LifePo4 16S 150A Smart BMS). It's a new system that I have so I can't tell that it worked earlier and not any more.
Everything is online and 95% working fine for a few days now and each day the BMS stops charging around 70-75% SOC.
My system consists of a
- Multiplus II 48/5000
- Solarpanels (not really relevent in this case because they are AC coupled)
- CerboGX
- SmartShunt
- 16S / 280Ah battery
- Daly Smart BMS 16s LifePO4 150A
- All sorts of fuses everywhere....

I don't really know what to explain more, all the system is charging fine, and the second after, the BMS stops charging (the Chrg MOS is off) without any information (no overvoltage or anything in the SmartBMS App). This happens every day during the charge, at random SOC (mostly above 70%).

I still have access to the BMS, and just need to restart it using the app and it's working fine again.

Any thoughts why this would happen ?

View attachment 134772

You don't explicitly mention having a solar charge controller.
Which one do you have?