Deye Hybrid 8kW curtails solar after battery is charged

I am having an issue with my Deye 8kW hybrid inverter (SUN-8K-SG01LP1-EU)

Problem:
After the battery reaches 100% charge, the PV power output immediately drops from 5-7kW to 0.15-0.5KW, even on clear, sunny days. Even if my house is using 3kW, the solar is curtailed to below 0.5kW, and 2.5kW will get purchased from the grid. This happens every day as soon as the battery reaches 100%. The solar output will be strong only before the battery reaches 100% charge.

System Details:
8kw hybrid inverter, 8.8kwp panels, 14.3kw lifepo4 battery, no net metering.

What I've tried:
I tried both "Batt First" and "Load First" in Work Mode 1, but it didn't fix the problem.

Pictures Attached.

Change "power" setting from 0 to 1500 (05.00-17.00) in "Time Of Use" table.

If you can backfeed grid enable "Solar Sell".

Edit. You can up all those "power" numbers to 7000 or similar as they are under 0,5C of your battery which is still very safe.

shadowmaker said:

Change "power" setting from 0 to 1500 (05.00-17.00) in "Time Of Use" table.

If you can backfeed grid enable "Solar Sell".

Click to expand...

The "Power" column refuses to go above 60 for the 13:00-17:00 timeslot. Like, I will press the physical Up arrow button and it will go from 0, 10, 20, ..., 60, and then it stops at 60 and refuses to go above. I can go back down to 0 from there. It's strange, because my installer was able to set 1500 or 1600 for some of the other timeslots.

Re: solar sell, I don't have a net metering arrangement so I can't do that yet.

diydeye said:

The "Power" column refuses to go above 60 for the 13:00-17:00 timeslot. Like, I will press the physical Up arrow button and it will go from 0, 10, 20, ..., 60, and then it stops at 60 and refuses to go above. I can go back down to 0 from there. It's strange, because my installer was able to set 1500 or 1600 for some of the other timeslots.

Re: solar sell, I don't have a net metering arrangement so I can't do that yet.

Click to expand...

WTF?

Do you have app (Solarman Smart or Deye Cloud)? I bet you can change those numbers from there. At least I seem to be able to change some settings higher using app than using Deye screen. Though never had any issues with power settings on TOU table.

Edit. Put something like 1500 to 7000 in every power slot it will allow. If 13.00-17.00 is only slot that is not allowed to go higher than 60, then change time of that slot from 13.00-17.00 to something like 13.00-13.05. This way it will draw power from grid for only 5 minutes. Still very strange though and you might want to contact your installer to get update for your Deye.

Just can't think any reason why it wouldn't let you change those power settings. @houseofancients

shadowmaker said:

WTF?

Do you have app (Solarman Smart or Deye Cloud)? I bet you can change those numbers from there. At least I seem to be able to change some settings higher using app than using Deye screen. Though never had any issues with power settings on TOU table.

Edit. Put something like 1500 to 7000 in every power slot it will allow. If 13.00-17.00 is only slot that is not allowed to go higher than 60, then change time of that slot from 13.00-17.00 to something like 13.00-13.05. This way it will draw power from grid for only 5 minutes. Still very strange though and you might want to contact your installer to get update for your Deye.

Just can't think any reason why it wouldn't let you change those power settings. @houseofancients

Click to expand...

We figured out how to put 1500 in each timeslot. We had to hold down the Up arrow instead of tapping it repeatedly.

Looks like it worked!!! Thank you!

@shadowmaker EDIT: What's the difference between 1500 and 7000? Practically what will this mean? Also should we keep it at 50% Batt in the last column?

diydeye said:

We figured out how to put 1500 in each timeslot. We had to hold down the Up arrow instead of tapping it repeatedly.

Looks like it worked!!! Thank you!

@shadowmaker EDIT: What's the difference between 1500 and 7000? Practically what will this mean? Also should we keep it at 50% Batt in the last column?

Click to expand...

Deye help desk was very helpful.

BATT field represent limit till which it will be depleted without using grid power. Below that limit LOAD will be supplemented with GRID if PV is not enough.

Tried it today and it works. I have set 12000 in power fields.

diydeye said:

EDIT: What's the difference between 1500 and 7000? Practically what will this mean? Also should we keep it at 50% Batt in the last column?

Click to expand...

1500 means that Deye will supplement your power needs max 1,5kW from battery. The rest needs to come from PV/grid. As you have 14,3kWh lifepo, 7000 means it can discharge max 7kW for your needs which is still under 0,5C rate (very safe with lifepo, you can use up to 1C =14300).

Batt percentage is how low you want to discharge your battery. If you don't need any emergency storage for blackouts, then 5-10% is ok, if you want to have always something left for blackouts, then 30-50% is ok. Just keep in mind that some premade batts have low SOC protection written in their BMS (=battery management system) that won't allow you to go under 10% or 20%, even you set Deye to go lower. To get around that you might need help from seller/installer. 5%-100% (3,1V-3,6V cell voltage) is safe with lifepo if charge/discharge rate is 0,5C or less.