XW Pro - charge/discharge in loop when voltage goes below 52

[ohsolar]

hi,

I have a charge block set from 6 a.m. to 8 p.m. but it triggers charging whenever the voltage drops below 52. I checked all settings and I don't see this set anywhere. Is this hardcoded? I have the latest version of the insight and xw software. It switches between charge and discharge continuously when this happens. I set the inverter in standby and back to operating to fix the issue..any ideas? This happens maybe couple of times a week.

thank you

 

[400bird]

What's the timeline on that? Does it last 10 seconds or 2 hours? What are your AC loads doing at the time?

 

[400bird]

To answer your question, no there isn't a hard coded recharge voltage setting.

 

[ohsolar]

It keeps on going until charge block end/load shave end (8 pm). I am working on some setup which alerts me, so I usually stop this event within 30 mins. AC load are between 200-400w. No solar, just TOU based

 

[400bird]

I guess I'm not seeing that. The graph shows one little spike of charging. Edit: not charging, the spike only goes up to 0 amps.
Any chance it is disconnecting from the grid?

The spike of 2000 watts discharging from the battery followed by touching 0 amps, doesn't look like a charge event to me.

Looks like a bigger load turned on, caused the battery voltage to dip below 52 volt, stop discharging (due to you settings) then the battery voltage recovered and it resumed covering your base loads.

 

[ohsolar]

>Looks like a bigger load turned on, caused the battery voltage to dip below 52 volt, stop discharging (due to you settings) then the battery voltage recovered and it resumed covering your base loads.

Interesting..30 or mins before the event I see a spike. Maybe it is not 52, maybe it dipped below 50 which is my recharge voltage. The charts don't show the dip below because of granularity? I am grabbing these every 15 secs(using modbus) for my custom dashboards..Grid is ok



These charge/discharge cycle stopped when I put the inverter in standby (about 10 mins)

 

[ohsolar]

I have SOC at 80% with voltage at 51.5. No issues, just wondering if ok based on attached chart. I dropped the recharge voltage setting to 51 and have not seen the issue mentioned above. Does recharge trigger on voltage even if SOC block is set?

https://batteryfinds.com/wp-content/uploads/2023/04/LiFePO4-Battery-Voltage-Chart-3.2V-12V-24V-48V_By-Battery-Finds.webp

 

[400bird]

You're SOC is probably inaccurate. The BMS resets/relearns when the cells high some specific high voltage.

When was the last time it fully charged to something around 57 volts?

 

[ohsolar]

You're SOC is probably inaccurate. The BMS resets/relearns when the cells high some specific high voltage.

When was the last time it fully charged to something around 57 volts?

hmm..it never charges to 57v. I have it set to 99% soc charge max. So when it is at 99% soc, the voltage is around 53.5

Today's:


Does recharge trigger on voltage even if SOC block is set?

 

[400bird]

hmm..it never charges to 57v. I have it set to 99% soc charge max. So when it is at 99% soc, the voltage is around 53.5

Hmm, I made a guess that you had Lifepo4 16s batteries. 57 volts would be 3.56 volts per cell.

I must have made a bad assumption, because 53.5 is 3.34 volts per cell. But the chart you posted looks like 16s Lifepo4
I also don't know your BMS or where specifically it relearns SOC.

Today's:
View attachment 193209
View attachment 193211
Does recharge trigger on voltage even if SOC block is set?

SOC block?

 

[ohsolar]

Hmm, I made a guess that you had Lifepo4 16s batteries. 57 volts would be 3.56 volts per cell.

I must have made a bad assumption, because 53.5 is 3.34 volts per cell. But the chart you posted looks like 16s Lifepo4
I also don't know your BMS or where specifically it relearns SOC.

I have the EG4 LL batteries and in closed loop with insight home.

SOC block?

I have a charge block from 6 a.m to 8 p.m. If the voltage hits the recharge voltage, would it trigger charging even if the charge block is set?

 

[400bird]

I have the EG4 LL batteries and in closed loop with insight home.

Those are 16s Lifepo4 packs. 53.5 doesn't seem anywhere near 99%
I'd charge higher, you aren't even getting into the area where the balancing should he happening.

I have a charge block from 6 a.m to 8 p.m. If the voltage hits the recharge voltage, would it trigger charging even if the charge block is set?

View attachment 193218

I see, the charge block timer should be absolute. No charging during those hours. I don't hit the recharge voltage ever, so I could be wrong. Try it out.

 

[ohsolar]

Those are 16s Lifepo4 packs. 53.5 doesn't seem anywhere near 99%
I'd charge higher, you aren't even getting into the area where the balancing should he happening.

I see all 4 lights on the eg4 batteries. I will check if they are really at 99%. You mean charge higher than 99%? Things break if I set to 100%(recommendation from SS is to set to 99%)

I see, the charge block timer should be absolute. No charging during those hours. I don't hit the recharge voltage ever, so I could be wrong. Try it out.

yeah, I have see it start charging even when the charge block is set. When recharge voltage was set to 52v, I was seeing it recharge/discharge. I then lowered it to 49v and have not seen the issue this week. Will need to watch for some more time.

thank you

 

[400bird]

I don't know EG4 BMSs just Lifepo4 cells.

3.34 volts isn't 99%

 

[JBertok]

This might help with some of the voltage setpoints. It's a slide I pulled from one of Schneider's videos that explains the points at which the XW Pro changes modes internally. The LBCO+1.0V is not a clearly documented setpoint, for example, and you cannot see it or change it but it is there.

 

[ohsolar]

This might help with some of the voltage setpoints. It's a slide I pulled from one of Schneider's videos that explains the points at which the XW Pro changes modes internally. The LBCO+1.0V is not a clearly documented setpoint, for example, and you cannot see it or change it but it is there.
View attachment 193237

Thank you..Will check it out

 

[ohsolar]

So I got the status from the batteries and they are charged at 98.3% and the cell voltages are all within .001v (in all 4 batteries). I have attached the status from one of the batteries. Is there a way to charge the batteries so the Voltage is higher at 99% SOC? cc @Markus_EG4

ref post which recommended 99%. I used to get F49 errors at 100% : https://diysolarforum.com/threads/eg4-battery-floating-at-58-4v.66391/page-2#post-939606

 

[400bird]

3.30 volts is not 98%
More like 50%, but it's hard to accurately translate from voltage to SOC

 

[ohsolar]

Looks like around 70%. So is this a bug? This data above is directly from the eg4 battery. @Markus_EG4

 

[ohsolar]

Interesting ..even in docs it shows with 97% soc, 53.19v (48v system)

https://eg4electronics.com/backend/wp-content/uploads/2022/07/EG4-Lifepower4-48V-Manual.pdf

cc some others: @EG4_Jared , @EG4_Jarrett