Batteries suddenly empty

[Charles B]

Hello,

I have a 16K Deye inverter with 5 CFE 5100S and one CFE 5100 batteries. All works fine until batteries reach about 54% capacity. Then they suddenly drop to 1%. Can anyone please help?

 

[MisterSandals]

CFE 5100S

https://www.cfenergygroup.com/ResidentialESS/345.html

How are you determining your battery was at 54% SOC?

Have any pics of your battery wiring or anything we might be able to get clues from?

 

[Charles B]

Batteries connected in parelel on busbars.

 

[Charles B]

https://www.cfenergygroup.com/ResidentialESS/345.html

How are you determining your battery was at 54% SOC?

Have any pics of your battery wiring or anything we might be able to get clues from?

was in front of inverter when this occured

 

[MisterSandals]

Looks like its showing 14% SoC in the pic, what is the corresponding voltage to that?

What happens when they drop to 1%?

I don't have any idea what is happening but if i were to guess, i would think that the SoC has drifted and is no longer accurate, perhaps because it has not been reset with a 100% charge or whatever resets the SoC.
I suspect the battery voltage at 54% SoC was at some critical setting on your Deye, perhaps a battery disconnect setting.

 

[Charles B]

Looks like its showing 14% SoC in the pic, what is the corresponding voltage to that?

What happens when they drop to 1%?

I don't have any idea what is happening but if i were to guess, i would think that the SoC has drifted and is no longer accurate, perhaps because it has not been reset with a 100% charge or whatever resets the SoC.
I suspect the battery voltage at 54% SoC was at some critical setting on your Deye, perhaps a battery disconnect setting.

Attached my Inverter Settings. If you can maybe look at them and see if you see anything plz.

 

[Charles B]

I took the picture after a while. That was why it was showing 14%. (Charging from grid)
When it drops to 1% it either switches to grid power if available, otherwise switches off the power to the house.

 

[shavermcspud]

Assuming all battery packs feed the single inverter? The cabling doesn't look correct, it appears you have them all wired in to single pair of bus bars then on the inverter. my hunch is in this config, you have one pack that is low and triggering the alarm.

Photo bellow, albeit a different battery brand shows how they should configured. inverter feed from each end of the pack.

 

[MisterSandals]

I'd still like to see the actual battery voltages at whatever SoC you would have. It would be good to see if the battery voltage is reasonable for any SoC.

In your settings, 1st pic, empty battery is 48V and battery shutdown at 10%.

Are there any log files or error messages that can be found in the Deye?

When it drops to 1% it either switches to grid power if available

If you can get the battery voltage when it drops to 1%, displayed in the Deye and a corresponding volt meter reading on battery 1, the master that would be REALLY helpful.

 

[Charles B]

Ok. Thx. I will post as soon as I am back at the inverter. Currently not there.

 

[shavermcspud]

The manual even shows the correct way to cable them for single parallel config

 

[Charles B]

Attached a screenshot from my phone on what happend

 

[MisterSandals]

Attached a screenshot from my phone on what happend

Do you have something like this that shows the battery voltages? That i believe will tell the story.

 

[Skypower]

You need to physically use a voltmeter along with recording the state of charge reported to see if the state of charge is correct. Preferably at several different SOC AND no or very low load. This method is only ballpark but should be close enough for now.

 

[Charles B]

Does this help?

 

[MisterSandals]

Does this help?

In your app, can you "select parameter" and display voltages? Or any of the data or device pages you can select on the bottom?

Gotta find the voltage and see it that is out of synch with SoC. Maybe we can find a way to reset it or recalibrate (but that might need 100% SoC, i dunno).

 

[Charles B]

In your app, can you "select parameter" and display voltages? Or any of the data or device pages you can select on the bottom?

Gotta find the voltage and see it that is out of synch with SoC. Maybe we can find a way to reset it or recalibrate (but that might need 100% SoC, i dunno).

Had a Look. Just shows Kw no Voltage.

 

[Charles B]

Does this help?

 

[MisterSandals]

Does this help?

Its shows something interesting in that 80% SoC is 60V and 40% SoC is 30V if i am reading the numbers on the left side correctly. I would expect 100% Soc to be just below 60V.
But i have no idea how this is supposed to work on your inverter.

On the graph, it looks like battery voltage is in the 50's and then for some reason just after 03:00, it drops drastically. Did anything in particular happen at that time?

I think somehow on the Deye you need to recalibrate the SoC with voltage. It looks like it drifted quite a bit and when your 48V battery is fully charged around 56-58V, the SoC is only about 75.
If you have a manual, perhaps it has a procedure for that?

 

[Charles B]

Its shows something interesting in that 80% SoC is 60V and 40% SoC is 30V if i am reading the numbers on the left side correctly. I would expect 100% Soc to be just below 60V.
But i have no idea how this is supposed to work on your inverter.

On the graph, it looks like battery voltage is in the 50's and then for some reason just after 03:00, it drops drastically. Did anything in particular happen at that time?

I think somehow on the Deye you need to recalibrate the SoC with voltage. It looks like it drifted quite a bit and when your 48V battery is fully charged around 56-58V, the SoC is only about 75.
If you have a manual, perhaps it has a procedure for that?

Thanks. Will have a look and come back to you if I don't come right.