Fronius Hybrid with Modbus TCP

[Tico]

Please leave comments or questions here regarding a loxwiki article at this link -

https://loxwiki.atlassian.net/wiki/x/cYJxTg

[Tico]

I have hit a snag with one of the Fronius Hybrid modbus commands - namely, putting the inverter into STANDBY mode. It has stopped working.

There are three possibilities I've considered -

1. A bug has been introduced by a Fronius firmware update;
2. A bug has been introduced with a Loxone firmware update; or
3. A hardware fault has developed in my inverter.

I can't tell the exact time when the STANDBY mode stopped working, but the timeframe could include all the above.

Can anyone confirm whether their system works to place the inverter into STANDBY using Loxone?

The specific register is called CONN. It's a read/write register that can have two values -

0 = STANDBY
1 = ON

The CONN register is being successfully written to and reflects the correct value from the modbus sensor. The inverter is not physically going into Standby when observed at the inverter.

[Tico]

To close the loop on this problem... The bug was introduced by a Fronius firmware update.

Fronius Hybrid firmware version 1.11.3-2 introduced the bug.
Version 1.12.1-10 fixed it.

bug fixes:
/ W-LAN: Signal strength got increased.
/ Modbus: Standby-function is operating again.
/ Modbus: Register "WMaxLimPct_RmpTms" is writeable now.
0x0000 and 0xFFFF gets interpreted as "as fast as possible".
/ Service Message 65000 is now shown for BYD batteries.
/ DC injection measurement has been improved.

[19domi89]

Where do you geht the Whole modbus register with all adresses?
Can you upload this file?

[Tico]

Go to the Fronius Download Search at -

https://www.fronius.com/en/photovoltaics/downloads

Search on 'Modbus Sunspec Maps'. The zip file has all the Fronius models. The excel spreadsheet called 'Inverter_Register_Map_Float_v1.0_with_SYMOHYBRID_ MODEL_124.xlsx' is the one you want. The tab 'Complete Map' has the specific register numbers.

Also, spreadsheet 'Meter_Register_Map_Float_v1.0.xlsx' has the register numbers for the Smart Meter. Also use the 'Complete Map' tab.

[19domi89]

Thank you!

But i don't find this adresses. In the forum you wrote 40091 is the AC Power of the normal Symo.
Can i get the AC Power of String 1 and String to also?

The same i would like to read out with Symo Hybrid.

THanks.

[Tico]

AC_Power only exists for the Hybrid as a singular total value.

The first input into the Hybrid is the solar panels. They are only Direct Current (DC). The value to read the panels is 1_DCW. The Hybrid has only one input for solar panels. You might physically have two 'strings' of panels on the roof, but they will be wired in parallel into DCW_1. You cannot determine what each individual string is producing.

The second input into the Hybrid is the battery. It is also only Direct Current (DC). The value to read the battery is 2_DCW.

DCW is the sum of 1_DCW and 2_DCW.

For interest, you can compare the losses in the DC to AC conversion by comparing DCW and AC_Power. This can be a significant loss when high loads are encountered.

[19domi89]

In my energymonitor its only okay when i take the AC Power value, otherwise its not like in the solarweb. So i have to take the AC Power and not the DCW i think.

Ist there a second or third AC Power value in the symo 6.0.3?

[Tico]

No, there won't be a second or third AC Power value in the Symo 6.0.3.

In the Symo 6 you will have 2 solar inputs (MPPT's). They represent two independent inputs and can both be read. They are also DC values.

1_DCW - String 1
2_DCW - String 2

The AC_Power value is after conversion from DC to AC of all inputs.

For the Symo Hybrid, I use 1_DCW for the input to the energy monitor (Pp). It exactly matches solarweb.

[mgerste]

Hello, I have everything set up according to instructions. Everything looks good during the day and while the battery is discharging. However, if the battery is empty and no electricity is produced, does the variable 1_DCW always show 655.4 W?

[Tico]

I have that issue with the variable ChaState (battery state of charge). That goes to 655.4 when the battery is empty. It can be fixed with a Status block as depicted below.

[mgerste]

Hello, unfortunately it doesn't work. Can it have to do with the fact that I activated the emergency power function. The minimum soc is set to 7%.

[Tico]

I don't have the Emergency Power mode activated. I'll have a look tonight and see what settings are available for a work-around.

The value 655.4 is effectively the 'sleep mode' of the inverter with a null output. You could try the settings in the attached picture to see if these keep the inverter alive.

[Tico]

Ignore the previous post. I already had a work-around for the 1_DCW problem buried in a different part of my config. I'd forgotten about it, sorry! The Emergency Power mode is not relevant.

The best description is in the attached pictures -

1. When the inverter is shutdown, it shows a status (Hybrid Modbus sensor StVnd) of value 3. That's when it outputs the 'null' output of 655.4 W.

2. A Status block intercepts when StVnd = 3 and modifies the 1_DCW output to 0 watts.

3. There's an extra work-around here to deal with spurious 1_DCW values that occasionally occur. If the 1_DCW value is greater than the solar array can produce, it instead replaces the value with a 5 minute moving average. If you are keeping statistics of solar production, this keeps the graph 'nice' and prevents spurious high values distorting the scale.

[Tico]

Sorry, but I don't understand the question?

[19domi89]

The StVnd value is the operating State of the fronius Symo. What does the value 3 tell us? And which values are possible for StVnd and where can i see the possible values?

[Tico]

Answer in post #42 -

https://www.loxforum.com/forum/faqs-tutorials-howto-s-aa/132379-fronius-hybrid-with-modbus-tcp?p=272573#post272573

[mgerste]

Hello, thanks for the instructions. I'll try it out on the weekend. Maybe you can post the workaround as a project file. Unfortunately, I am not that skilled and would find the right building blocks faster. Thanks for the support.

[Tico]

The work-around is part of my 'whole-of-house' loxone project. The screenshots should provide all the detail you need.

Otherwise, give a shout out and I'm sure I can clarify anything.

[mgerste]

Hello, can you please explain the element with the heading 5 min average to me. Which element is it and how should it be set? I think I got the rest of it. Thank you

[Tico]

Moving Average block
Remanence input - checked
ST = 10
S = 30