Deye Inverter selling to grid from battery

[lucize]

Recently I am able to sell to grid but it seems that the Deye inverter will sell from battery to grid if the BMS sends the "Wait" (Discharge) CAN message.
Did somebody faced the same issue ? If the battery is set on Voltage or Voltage % mode this will not happen, but the battery will be always be kept at 100% while solar energy is available.

I'm thinking to make a change in the script so after the absorption time the charge current to be set to 0A and the state to go to Bulk instead of Wait.

Deye technician is saying that the voltage drop is too large from the Absorption voltage and that's why the inverter is selling the battery so it can discharge based on the voltage it reads. So it will drop from 56V to somewhere to 53.8V - 53.9V. Is this a normal voltage for 16s lifepo4 ? or the connections to the inverter are bad ? Scanned with infrared and the battery terminals are the same as battery temperature (25-29 degree celsius)

[Uksa007]

There are many Deye users and no one else has reported this, are you sure you have the inverter configured correctly?
It doesn't seem logical that it would sell battery power into the grid unless the inverter was configured that way.
Are you using the Time of use(TOU) settings? There maybe you have some issues with it's configuration?
I have also seen many Deye bugs in their firmware, are you running the latest version in the Deye?

The charging status, Bulk and Wait are just informational, they don't get sent to the inverter.
When the changing status is wait, it sets the charging current to 0.

Deye technician sounds confused, if the battery voltage is lower due to is SOC say 50% will it start selling then, based on its lower voltage, that makes no sense to me.
Is the battery voltage in the BMS the same as the real battery voltage, measured with a multimeter, and it is the same as the Deye sees/displays? If not you can calibrate it via the JK-BMS app?

[lucize]

Yes it's strange no one has reported this and can't find anything related to this issue. it's is supposed to sell from battery if "sell first" is selected but otherwise it shouldn't. I have zero export to load and solar sell selected, also time of use is selected to drain the battery until 10%. Confirmed with them that is the right setting as I sent a video of the setup.

The voltage is almost the same as at the battery and what the bms shows, I guess I lose ~2-4mili volt with the length of the cables and the breakers from the battery to the inverter

So, setting the charge to 0A from the bms slider works good, but the status need to be bulk, otherwise it will sell from battery. I think that until they find the issue (if ever, I'm on the latest firmware, they updated it) I'll have to set absorption for hours and automate the change of charge current to 0A. Here I don't understand why it's working if you say that only the charge current is set to zero when in wait mode

[lucize]

VID_20231014_142549.webm

[Uksa007]

In the video on the System work mode, you have solar sell ticket twice, should only be one, try without using TOU setting (remove tick at top of TOU page)

Are you using my interface kit?
If you want one on one support to diagnose and write workaround code for your specific issue, please consider subscribing to the Dedicated support membership.
https://www.patreon.com/checkout/Uksa007Codedevelopment?rid=17047031

[straga]

Yes, Deye with BMS work very bad. Need external device for control that. Or how do many people leave like is.
for example 0 amp for dischard for Deye no 0. Any way grab energy from battery and sell it. if percentage SOC more that we set in System Work Mode.

[lucize]

the good workaround is to keep absorption on and after a timer set charge to 0A but still keep absorption state, then when bulk kicks in, set charge to default. At the moment didn't had time to test it directly in esphome, I'm doing it from automations.
Maybe not many people that are using esphome and jk bms are selling to grid

[Uksa007]

I believe I have resolved these issues in the latest firmware:
https://www.patreon.com/posts/92562386

[lucize]

Using the float script seems to be ok, and it will not sell

[straga]

Can give example for float script.

[Uksa007]

It is fixed in my firmware, no need for any scripts.

[lucize]

.

[straga]

@lucize Thanks a lot.

[Uksa007]

Pretty sure will cause the battery to microcycle, or saw tooth charge constantly from Float to Bulk/absorption voltage.