Modbus over LAN/TCP port 502

[mcmellow]

In july 2016 SolarEdge published a document https://www.solaredge.com/sites/default/files/sunspec-implementation-technical-note.pdf on sunspec protocol. According this document you can read modbus over LAN/TCP using the port 502.
In this mode, the inverter will still be communicating with the SolarEdge server so monitoring services and firmware updates will still be available. Is it possible to add the communication mode to semonitor.py?

Kind regards
McMelloW

[jbuehl]

The Sunspec protocol does not include any of the module (optimizer) level data because that is proprietary to SolarEdge. That's the reason this project was created (see the README). There are a number of data logger products available that will read this data https://sunspec.org/sunspec-certified-products/. If someone wants to write a program that processes this protocol I'll add it to the project, but it won't be able to produce all the data that semonitor.py does.

[lesinigo]

I have looked into using the Modbus over Ethernet (TCP) support of my SolarEdge HD Wave inverter, but I quickly found out that when you configure the inverter for that protocol it will wait for a connection for up to 120 seconds and if your modbus tcp client does not connect in time the inverter will just give up and never listen on TCP again. The same also holds true if your client is connected but goes down for whatever reason (eg. system reboot), it will have just 120 seconds to reconnect.

When that timeout passes by you won't be able to put the inverter in listening mode again if you only have an Ethernet connection: you will have to physically go to the inverter and reconfigure it.
I didn't check if it is possible to reconfigure Modbus over Ethernet through a serial (RS232 / RS485) connection, but if you have serial you shouldn't need ethernet anyway.

This 120 seconds thing makes it unreliable (in my opinion) for unattended operations, so I just gave up the Modbus over Ethernet option and will try to use the RS485 connection.

Reference: https://www.solaredge.com/sites/default/files/sunspec-implementation-technical-note.pdf (look for the "MODBUS over TCP Support" section).

Hope this is useful to you guys.

[lesinigo]

I have looked into using the Modbus over Ethernet (TCP) support of my SolarEdge HD Wave inverter, but I quickly found out that when you configure the inverter for that protocol it will wait for a connection for up to 120 seconds and if your modbus tcp client does not connect in time the inverter will just give up and never listen on TCP again. The same also holds true if your client is connected but goes down for whatever reason (eg. system reboot), it will have just 120 seconds to reconnect.

When that timeout passes by you won't be able to put the inverter in listening mode again if you only have an Ethernet connection: you will have to physically go to the inverter and reconfigure it.
I didn't check if it is possible to reconfigure Modbus over Ethernet through a serial (RS232 / RS485) connection, but uf you have serial you shouldn't need ethernet anyway.

This 120 seconds thing makes it unreliable (in my opinion) for unattended operations, so I just gave up the Modbus over Ethernet option and will try to use the RS485 connection.

Reference: https://www.solaredge.com/sites/default/files/sunspec-implementation-technical-note.pdf

[dave92082]

For what it's worth, I'm not sure if the new inverter firmware has addressed the issue that @lesinigo was seeing however I was able to connect (and re-connect) via ModBus TCP reliably since my SE5000 was installed last week.

I can still only have one device communicating to it at a time but aside from that, I have made many connections to try and scrape all data available. I created a Prometheus exporter to populate a Grafana dashboard with stats every 5s and it has been running for a week without issues.

Beyond the SunSpec data, I did find additional holding registers with data in the 60000 range however I have not been able to make a correlation if its module data or not. Feel free to check it out if you are looking for real-time inverter data (without modules): https://github.com/dave92082/SolarEdge-Exporter

[marpi82]

There is also original Sunspec python library written by Sunspec team HTTPS://github.com/sunspec/pysunspec/ and it is working with SE inwerters as with the other Sunspec enabled inverters (meters, baterries etc.)

[mulles]

@marpi82 did you run into the 120seconds issue by lesinigo ?
@lesinigo According to #124 (comment) their might by a way to remotely "reset" the setting ? Had no chance to try it out myself!
edit: -> remote configuration via local API only available when SetApp (Android App) is supported by the inverter (common on the new ones)

[marpi82]

@marpi82 did you run into the 120seconds issue by lesinigo ?

No, on my inverter I didn't have this issue. I can connect enytime I need. Sometimes I was disconnected couple days and made connection without problems

[dave92082]

Same here... every time I tried to connect, I was able to grab a socket. I think the firmware on the later inverters have addressed that problem

[mulles]

@dave92082 @marpi82 thx for sharing. Could you state, which Inverter Models you are using and maybe even firmware version?
Or at least if they still have an lcd display?

Much appreciated :)

[dave92082]

@mulles

My inverter still has the LCD screen. It is a SolarEdge SE5000 w/ CPU version 3.2221.0

Further details regarding how I access it and open the TCP socket can be found here:
SolarEdge Exporter

[mulles]

@dave92082 thx, that great news for me, even more that you have some code ready :)

Last question: Even though reconnect after connection loss works now. The requirement to do the intial connection ( first connection ever) within 120seconds (2min) after activation Modbustcp via inverter screen is still mandatory?

[dave92082]

@mulles, no, after my solar company installed the inverter it was at least 12 hours before I attempted to connect tot it from code. My network has also gone down (upgrades,etc) since then and I have never had a problem establishing a connection.

To date I have never had a problem connecting to the inverter with a single socket. The only problem I have had is if I forget to disconnect my prometheus exporter from the server while I try to debug on on PC. It does not seem to handle multiple connections however single connections (regardless of the disconnected time) are no problem.

The inverter has never been powered down and I have been able to connect to it with no problems throughout all of my experimentation.

[marpi82]

@mulles
I have model without LCD.
For more details You can look at https://github.com/marpi82/sunspec_test/blob/master/modsunspec/result.txt. Only problem I have is wrong LL voltage level read from meter - I have created RMA on SE Support and waiting... becouse when I connect directly to meter by USB->RS485 converter all values are ok.

[mihailescu2m]

Mine works quite well too - with the screenless inverter.
I do have an issue connecting (using the sunspec python module) - if I try to read the data immediately after making the connection, I get an error - so I have to wait for 1s after making the initial connection before actual reading data. After that, I am reading new values every 15 seconds without problems.

I am trying to aggregate the data to look like the one in the official API call for inverter technical data (https://www.solaredge.com/sites/default/files/se_monitoring_api.pdf page 35). So far almost everything matches (minus cosPhi and groundFaultResistance which are missing) except the powerLimit % - modbus data has powerFactor % but I don't think they are the same. Maybe powerLimit is DC_Power*100/AC_Power? Thoughts?

Finally - I can get optimizer data at 15-min intervals with a script that parses the monitoring website (from Layout/Playback), so this could be a good alternative for monitoring since it's not invasive and doesn't require any extra hardware, all software.

[dragoshenron]

@mihailescu2m
The power factor is the cos phi. Same thing.
My bet would be that Powerlimit is simply the % relative to rated AC power.