Sunsynk (DEYE) Hybrid Inverters

Thanks,

I'm going to enable grid charge and up the amps to 100 in battery settings.

I'll use the ToU menu to limit the charge to 2500W until oct/nov, after full 5000w charging power.

@graememk if you are running your inverter with overnight charging can you validate bellow settings for a 2-6AM grid charging (up to 2500W for now)

If I lower in battery setting the grid change A will it also limit the max charging power in ToU menu?

A quick update.
Inverter charged the battery as defined in ToU with a 50A current.
This morning I was exporting before 8AM. Usually it would export later after 10 - 100 depending on the weather(It was cloudy most of this or last week).

Ok so its not just me. Looks like there's some wonky code in the Deye charging algorithm. I have the JK settings as per Off Grid Garage and this is not working for me, batteries sit on Bulk charge all the time and never reach target because of the deye -0.5 volt offset. So batteries never reach 100% SOC, don't balance and no bulk/absorb/float. Wish I knew this before I swapped out my old Sofar inverters to Deye!

There is a thread on this on the DIY solar power forum here:

https://diysolarforum.com/threads/deye-weird-voltage-behavior-when-time-of-use-is-enabled.80908/

Its mentioned you can use an ESPHome module that's been developed to apply an offset to the CANBUS set-points from the JK to BMS

I'm going to try messing with the voltage calibration in my JK, and I'll try changing the Deye to battery voltage mode, which all feels like a big step backwards

I always use voltage as the SOC calculation of whatever BMS is brutal and prone to errors. In particular stopping discharging as it thinks SOC is too low, which means buying very expensive day rate electricity from the grid. No thanks!

I think I’m making progress. I'm suspicious of the Deye because when I don’t have TOU ticked it gives me the charge voltage the BMS asks for, and when I do have it enabled then it gives me 0.5 volts less than what I ask for. This is important if you’re using a JK Inverter BMS because its the same parameter used to request the charge voltage from the inverter that is also used to trigger the change from bulk to absorption and initiate the SOC reset. So if you don't reach target, the JK will not work as intended. I found it really noticeable when I was trying to charge to 55.2 volts because the Deye will charge up to exactly to 54.7 volts and then sit there until sundown. I saw exactly the same behavior when trying to charge to 55.8 volts, the Deye charged up to exactly 55.3 volts. I think what is going on is the Deye is just being conservative in its charging and you need to push it more into the area of exponential voltage growth, 56+ volts seems to work (as graememk suggested). It is important to know also that the Deye seems to discharge the battery if the battery voltage is over the requested charge voltage. So with the target of 56 volts, when the battery voltage gets near 55.5 my Deye seems go to into a loop of charge/standby/discharge, the voltage nudges up and after some minutes the JK will get a blip of 56 volts and trigger its timer for absorption and SOC reset. When the JK switches the charge voltage request down to the float voltage, my Deye will discharge the battery to reach this target. Yesterday was full sun all afternoon, my batteries were 100% by noon but then discharged by the Deye to 92% by late afternoon. So today I have also increased the float voltage setpoint to prevent such a big discharge. Maybe this is a waste of time and I should just charge on battery voltage but I will continue to tweak setpoints and post findings later if any interest.

@SD_DRACULA Do you use voltage with your battery or do you take the percentage from the Smart Shunt? Is there a big difference between the JK reported SOC and the Shunt?

I've purchased a esp32D board and max485 ttl converter to connect my Deye inverter to home assistant but not sure how compatible this 2 are.

ChatGpt say they are incompatible esp32D board runs at 3.3V while max485 at 5V.

Does anyone uses this setup to connect Deye invertor to home assistant?

Today I tried running on battery voltage and guess what…. The Deye still has the exact same behaviour. With TOU ticked the actual target Deye charge voltage is 0.5 volts less that what is set in Absorption V. The trigger to start the absorption timer seems to be (Absorption V – 0.5 volts) so it does start the timer which seems to be 30 minutes. Then it switches to Float V, where the actual target charge voltage again has the offset (Float V – 0.5 volts) ! If you switch off TOU then the 0.5 offset is not used. Its totally baffling. Also to point out that charging on battery voltage, when it switches from Absorption to Float it seems to discharge the battery at max watts until the float voltage is achieved! When I was running of ‘Lithium’ this discharge rate seemed to be limited to 150 watts. As far as I know the charger should not actively discharge the battery between Absorption and Float! this seems like total nonsense!

On the plus side I've got my second Deye connected and working in parallel despite the weird charging!