Hello. 

I have a 5kw Sunsynk inverter connected to a 12kwh Felicity battery (and the grid, and solar panels). This setup has worked well for the last 3 months or so, and the inverter communicates well with the battery, so I use the ‘Lithium Battery’ setting.

The energy supply priority is as follows:

solar supplies what can; if it cannot, battery supplies down to 25%, thereafter grid supplies. 

 

On the 1st December my inverter suddenly started charging my battery from the grid at 1420 in the afternoon, took the SOC to 100%, and then stopped logging data to the app. We did not notice any of this as our power supply was fine during this period. It resumed logging data at 1155pm. 

I just thought it lost WiFi connectivity or something. But since then, my supply priority has changed. Now, the grid keeps the battery at 100% at all times. If there is solar, my grid usage diminishes, and if there is not solar, my grid usage increases. The only time my battery supplies energy is during load shedding, at night. 

I don’t understand how behaviour can just suddenly change like this. I am the only person with access to the setup and I did not touch it. 

So, questions - 

1. Has anyone else experienced sudden changes in power supply priority with Sunsynks in the last week?

2. Any advice on how I can get behaviour back to normal? I’ve poked around a bit, but nothing has worked thus far. 

 

Is your timer still ticked under system mode? Maybe show your system mode setup screen? The system app not showing up to date information is nothing new since they have issues with that service every now and then.

For sure, I’m aware that the app is flakey. The timing is just a little suspicious, so I thought I’d mention it. 
 

Here is my system mode screen. Unchanged for the last 3 months. 

currently I am dealing with this by just turning off the grid, but that will bite me next rainy day.

 

Edited December 3, 20232 yr by riazarbi
Typo

Set the first start time to 00:00,

People have had strange issues when the first time slot doesn't start at 0.

Maybe try disabling timer and re-enabling  thereafter. 

As a last resort try update the firmware or factory reset the inverter, should fix it. 

Alright, I’ll give it a shot. A bit unnerved that this sort of thing could happen out of the blue. Hopefully changing the times will fix it!

21 hours ago, riazarbi said:

For sure, I’m aware that the app is flakey. The timing is just a little suspicious, so I thought I’d mention it. 
 

Here is my system mode screen. Unchanged for the last 3 months. 

currently I am dealing with this by just turning off the grid, but that will bite me next rainy day.

 

Did your installer perhaps remotely update the settings?

Unrelated to your issue:
Is the 2000/4000 the "inverter limit"?
I would expect this to be 5000W.

The 2000/4000 is the wattage limit that the grid is allowed to supply if the battery falls below thie percentage state of charge. When the timer is used for charge mode this limits the amount of current that will flow from the grid. I use 2000/4000 to limit how much I spend from grid charging. 
 

Installer says they didn’t make any changes. Turning off Grid Charge has stopped my battery getting sent to 100% from grid perpetually. But it also means if my battery dips below the timer limits due to load shedding the inverter will not use the grid to bring the battery back up to the desired state of charge - it will just ‘limit the drain’ by supplementing from the grid until the sun can bring the state of charge back up again. 

10 minutes ago, riazarbi said:

The 2000/4000 is the wattage limit that the grid is allowed to supply if the battery falls below thie percentage state of charge. When the timer is used for charge mode this limits the amount of current that will flow from the grid. I use 2000/4000 to limit how much I spend from grid charging. 

No, this is something else. The Power column is the maximum allowable power from the battery during the respective time periods.

Just thinking out loud here. Could it be that the sudden battery charge from grid was an equalization charge? Check under the battery settings whether it happens every 30 days, and if so, maybe you just missed the first few times it happened.

That was my initial thought. But it persisted for several days, which I thought was too long. Although, with these high levels of load shedding, maybe it could never get to ‘equalised’?

Also, thanks for schooling me on the Power column! I had an incorrect assumption on that one.

11 hours ago, riazarbi said:

The 2000/4000 is the wattage limit that the grid is allowed to supply if the battery falls below thie percentage state of charge. When the timer is used for charge mode this limits the amount of current that will flow from the grid. I use 2000/4000 to limit how much I spend from grid charging. 
 

Installer says they didn’t make any changes. Turning off Grid Charge has stopped my battery getting sent to 100% from grid perpetually. But it also means if my battery dips below the timer limits due to load shedding the inverter will not use the grid to bring the battery back up to the desired state of charge - it will just ‘limit the drain’ by supplementing from the grid until the sun can bring the state of charge back up again. 

Is your battery & Inverter communicating correctly - this can be checked on the LiBMS screen.

What are the values in the Batt Type/Batt Charge/Shutdown - these are mine for an 8kW SunSynk.

The first panel 150A*48V = ~7,200W is what the battery can accept (eg from PV) - the LiBMS does override these values.
The 2nd panel 50A*48V = ~2,400W (Batt Charge) is max allowed from the Grid.

EDIT: How many PV panels/Watts do you have?

Edited December 4, 20232 yr by system32

Just following up on this. 

To answer open questions:

1. My BMS was communicating correctly
2. Batt Type > Charge, discharge amps were set correctly
3. Batt Charge > Amps was set correctly
4. Shut Down settings were correct
5. I have 5kwp panels, a 5kw inverter, and a 12.5kWh Felicity battery.
6. Equalisation was originally at 90 days, but I set it down to 0 and did a full reboot and waited a few days - no effect.

I experimented with totally turning off everything related to charging - gris charge, grid signal, timer, unchecked all the timer boxes etc. Nothing worked - the grid would keep the battery at 100% no matter what. 

I waited for 2 weeks in this situation, disconnected from Eskom. 

Turned on Eskom again, it went right back to 100%. 

I finally requested a firmware upgrade, from 3.3.8.4 to 3.3.8.5. 

Immediately upon application of firmware and reboot, old behaviour was restored, and inverter works as expected. 

I'm pretty confused about how a component's behaviour can change _before_ a firmware upgrade, only to be fixed with a firmware upgrade. Reminds me a bit of this story https://www.404media.co/polish-hackers-repaired-trains-the-manufacturer-artificially-bricked-now-the-train-company-is-threatening-them/ (which is a wonderful read)

Anyway, is there any was to back up my sunsynk's settings? I can see there is an upload function. I'd like to back up the settings now, so I can restore if behaviour changes again.

1 hour ago, riazarbi said:

Anyway, is there any was to back up my sunsynk's settings? I can see there is an upload function. I'd like to back up the settings now, so I can restore if behaviour changes again.

I am not sure about a backup but I use the method of taking photos of each config section and page and store the photos. It makes it easy for me to quickly compare and also share my settings with others.

8 hours ago, riazarbi said:

Just following up on this. 

To answer open questions:

1. My BMS was communicating correctly
2. Batt Type > Charge, discharge amps were set correctly
3. Batt Charge > Amps was set correctly
4. Shut Down settings were correct
5. I have 5kwp panels, a 5kw inverter, and a 12.5kWh Felicity battery.
6. Equalisation was originally at 90 days, but I set it down to 0 and did a full reboot and waited a few days - no effect.

I experimented with totally turning off everything related to charging - gris charge, grid signal, timer, unchecked all the timer boxes etc. Nothing worked - the grid would keep the battery at 100% no matter what. 

I waited for 2 weeks in this situation, disconnected from Eskom. 

Turned on Eskom again, it went right back to 100%. 

I finally requested a firmware upgrade, from 3.3.8.4 to 3.3.8.5. 

Immediately upon application of firmware and reboot, old behaviour was restored, and inverter works as expected. 

I'm pretty confused about how a component's behaviour can change _before_ a firmware upgrade, only to be fixed with a firmware upgrade. Reminds me a bit of this story https://www.404media.co/polish-hackers-repaired-trains-the-manufacturer-artificially-bricked-now-the-train-company-is-threatening-them/ (which is a wonderful read)

Anyway, is there any was to back up my sunsynk's settings? I can see there is an upload function. I'd like to back up the settings now, so I can restore if behaviour changes again.

On the issue of remote hacking, I actually do worry about that & have always wondered how to have data being captured locally & only use Wi-Fi datalogger only for firmware updates. 

7 hours ago, Moffat said:

I actually do worry about that & have always wondered how to have data being captured locally

This is easily done via Home Assistant, look in my signature for more details