Hi Richard
Since the update my stp 20000-tl30 is loosing connection everey day.
My stp 8.0se keeps working fine.
If I reset the app, connection is comming back 9 out of 10 times.
How can I solve this problem?
Thank for help
Same sort of problem over here, but in my case itâs not daily. Inverter type is: STP 5.0-3AV-40
Iâm having the same problem. Only installed the SMA Energy app last week, never got it to work properly.
When restarting the app it works for about an hour, then loses connection I assume. Iâve been producing energy all day but only displays generation for 1 hour after resetting the app.
The inverter is a SB 3.6-1AV-41. I can share a diagnostics report or share more info if that is of use.
Habe the same problems,
For the time being, I restart the app every 3 hours automatically
I have improved the reconnect logic and released a new test version. The problem you may have experienced has been related to temporary connectivity issues between your homey and your inverter. The app previously failed to reconnect; I hope it works better now.
I also removed the battery capabilities for the inverter device type; use the battery device type as well for hybrid inverters. This means that for a hybrid inverter, you add both an inverter and a battery device, each with their respective capabilities.
This allowed solar power to be visualised properly in the Homey energy tab again.
1 Like
Hi,
I was using the set output power last Sunday to mitigate negative electricity pricing. But after a few minutes, my Inverter is stuck at 404W. I cannot reset back to max value or change to any other value from the Homey app.
If I logon to the inverter as installer, the grid export value is at max. If I try to change the value to something else, it saves OK. But the value is still max.
In the eventlog of the inverter, i have a ton of error like this â10120 currently permitted number of parameterizations exceededâ.
Checking the SMA support web, they only refer to contacting my installer. Iâve done that, waiting for a reply.
Now I just found this thread in a HA forum talking about this. Apparently some values are not supposed to be written to frequently as it will destroy the flash memory. They refere to a manual where some modbus register have yellow exclamation mark saying âWarning against cyclical writingâ.
I do not have that manual, but you might? Can you verify if the register you are writing to have that warning attached to it?
Post 13 and 19 are relevant.
It seems like my inverter might be bricked because of this. Until this has been confirmed, I would strongly recommend everyone stopped using the function to change output power of the inverter.
Iâve got an STP10.0-3AV-40.
I found the modbus parameter documentation. Register 40915 is indeed listed with the yellow exclamation mark that warns about cyclic writing 
Just wondering, when one only changes the active power limit to X Watts during negative prices, one canât cycle write this parameter? Iâve had negative prices for only a few days this year.
Unless youâd like to adjust the active power limit dynamically, to only use solar power without exporting power.
Is that the way you like to control it? That would mean it can get adjusted on every change in power usage, which can be every second with certain P1 meters.
I just limit the power to a generic home-usage level (around 400W at my place) at the hour the price becomes negative, and remove the limit when prices are positive again
Everyoneâs use case is probbaly different.
I do dynamic balancing on all charge boxes, if enabled. On load balancing and excess sun on negative pricing.
I also live in a place where we have scattered clouds quite often.
I also live in a part of the world where temperature fluctuates over the year.
And with that, a lot of applicances that consume electricity âat willâ.
So, for me, setting a base load at 400W would be one way of doing it. But I chose the dynamic route for all my automations, not just electricity related.
So in this particular case I check and adjust, if needed, every 6 seconds. 10 times a minut. 600 times an hour.
Obviously, I would have done it differently if I had known. But I didnât and currently that will cost me way more than saved on not selling excess power during negative pricing.
Itâs not really about how you use the function. The fact is, if you use it, you will eventually brick your inverter.
Iâve noticed you removed the slider from the device for some reason. Itâs only possible to set the power by flows now.
This seems to differ between inverters; either some only miss the warning in the documentation, or they behave differently.
The HA thread appears to discuss the Sunny Boy Storage and its control over charge and discharge. When you reviewed the Modbus specification for your inverter, did you find any relevant Modbus registry for limiting power? That doesnât use flash for storage.
Getting the error you got, I guess, doesnât mean a brick? That is why there is an error, to prevent a brick, I assume. The slider was removed, as mentioned in a comment above, because it was very hard to use, limited by the UI components offered by Athom.
Electricity is billed by the hour, but this will change to 15-minute segments this autumn. I see no practical reason for changing the power every six seconds, whether using flash or not. Companies like Tibber, which control vehicle charges among other things, manage them in intervals of several minutes.
99.9% of all RW registers have the warning to them.
Until your assumtion is a proven fact, itâs a brick.
I guess you need to graph your energy use to know what your consumption pattern is. In my case this is an example from today:
Orange is sun.
Yellow is battery (managed by Tibber)
Blue is house consumption.
Purple is import/export at the grid point.
So if today I had max sun and charged the car on excess solar. Blue and Orange would follow and Purple would be flat at 0.
If it would be a case of negative pricing, Orange would follow the Blue line and Purple would be flat at 0.
As you can see, setting a 400W flat solar production for 1 hour would not really do much.
This is how Homevolt battery is working when itâs scheduled for charge/discharge at grid setpoint 0. Homevolt adjust 60 times a minute.
But non of this is relevant. Only the fact that if the users inverter is writing to flash. It will brick. Just as the old Tesla Model S.
If I was the one responsible, I would take imidate action to prevent this issue from happening for the users of the app. Iâm not blaming you, if you didnât know about this issue. But now you know.
I have already released a new update that includes a hint for the action, warning that it shouldnât be used frequently because of FLASH. However, I am unsure how many users will notice this hint and take note of it. The only other option is to remove the action entirely.
Great!
I have a case with SMA, letâs see what they come up with. Hopefully there is a way to restore and at least unbrick the Inverter. Iâll keep you updated.
1 Like
Edit: Adding the SMA error code for google to find.
10120 Currently permitted number of parameterizations exceeded
Read the last 1 day of conversations.
Got a reply and a really great explanation of the issue by SMA support:
The flash memory of the inverter can be destroyed by too many parametrizations in specific sections. This event is triggered to protect the inverter hardware by blocking further parametrization.
The event is triggered after 1000 parameter changes. Once triggered the parameter changes are limited to 1 change per 20 operation hours. This is to protect the hardware from final damage.
Example: If the inverter counted 40 operation hours after the event, then 2 further parameter changes / settings are possible.
The number of changes was calculated for the complete lifetime of the inverter.
2 Likes
I found a way to limit export power to zero feed in.
If you have a homemanager 2.0 you can write 0 to register 40016.
0 means zero export, always taking self consumption in account.
After one hour it falls automatically back to 100 procent.
So you only have to write it two times in the hour.
Interesting, what settings do you have on your HM2? Thinking of these. If I only write to 40016, nothing happens for me, so I guess some settings need adjustment.
EDIT: Manually setting a max export in sunny portal works.
Do you write to registry 40016 on the inverter or on the HM2?
EDIT2: Writing it to the HM2 after enabling the grid management to Yes; then it works for me. Limiting of active power also needs to be enabled I guess, didnât try without it enabled.
Hi Richard,
First you have to put in a grid guard code to get the rights to write this register.
You must write it into the homemanager.
HM must have ID2
The strange part is that its a 16 bit register but you have to write it in 32.
EDIT: yes you have to enable grid management
I think there may have been a change here. The release notes for HM2 also state something along those lines.
Version 2.16.4.R (approx. April 2025)
Optimization of the Sunny Home Manager Modbus server: can be used without a Grid Guard code (GGC)
