Sunology PLAY2 connects in client mode but the proxy never gets data

[dca31]

Hi,

I'm trying to get client mode working with my TSUN micro-inverter (serial prefix Y47, so likely MS800/MS1600/MS1800/MS2000/MS2000-D range), part of a Sunology PLAY2 kit purchased in 2024. Integration target is a Home Assistant Green (HAOS).

Setup:

• App version: 0.16.0-rel (Home Assistant App, HAOS 18.2, aarch64/green)
• Inverter serial: Y47E8439081E01E5
• Monitoring SN: 2081xxxxx (happy to share full SN privately if it helps diagnose)
• client_mode configured: host 192.168.1.149 (local LAN), port 8899, forward = false
• Device has a static IP, ping works fine, port 8899 is open (confirmed via nmap)

Behavior:
The proxy connects successfully to the inverter (Connected to ('192.168.1.149', 8899)), then logs Testing sensor-list: 0x2b0 by reading modbus registers at 0x3000, but never receives a response. After ~28 seconds the peer closes the connection, and the proxy retries every ~10 seconds, looping indefinitely. No sensor data is ever received.

I've tried:

• Power-cycling the inverter
• Toggling ModBus Polling on/off
• Toggling Client Mode Forwarding on/off

Same result every time. Log excerpt:

[G3P:0] Connected to ('192.168.1.149', 8899)
Testing sensor-list: 0x2b0 by reading modbus registers at 0x3000
[inv_1/:0] Peer closed. for ('172.30.33.2', 37852)
[inv_1/:0] Connection closed - Shutdown: False

Is there anything specific about this model range that might require a different sensor-list ID, or a known firmware quirk I should check on my end? Happy to provide more logs (debug level) if useful.

Thanks so much for any input you could have.

[s-allius]

Hi @dca31,

which inverter model do you have exactly? I know that some don't replay on port 8899, even if they accept an incoming connection. Did you make a firmware update since 2024? Can you connect to the inverter's web-config? Maybe you can see a firmware-filename and the port configuration.

You should also check the trace log file, which you can download from the proxy's web-ui inside your Home Assistant.

[dca31]

Thanks for the quick reply!

• Exact model: still unable to find it on the device label or in the Stream app (only the Y47-prefixed serial and monitoring SN are visible). I've reached out to Sunology support directly to ask for the exact model and firmware history, will update once I hear back.
• Firmware update since 2024: don't recall doing one manually, and no update notification that I remember. Can't rule out a silent/automatic update though.
• Web-config: tried all combinations of http/https on ports 80, 443, 10000, 10443, 8080, 8443, plus the bare IP - all "connection refused" except port 8899 (which isn't browsable, as expected for a binary protocol port).
• Trace log: downloaded from the proxy's web UI. Here's the relevant excerpt - the proxy sends the request twice each cycle but never receives any reply at all (no incoming > lines):

2026-08-09 08:16:51  INFO |  msg | Testing sensor-list: 0x2b0 by reading modbus registers at 0x3000 
2026-08-09 08:16:51  INFO |  msg | <   Ctl: 0x4510 Msg: 'msg_command_req'
2026-08-09 08:16:59  INFO |  msg | <   Ctl: 0x4510 Msg: 'msg_command_req'
2026-08-09 08:17:29  INFO |  msg | Testing sensor-list: 0x2b0 by reading modbus registers at 0x3000 
2026-08-09 08:17:29  INFO |  msg | <   Ctl: 0x4510 Msg: 'msg_command_req'
2026-08-09 08:17:37  INFO |  msg | <   Ctl: 0x4510 Msg: 'msg_command_req'

This pattern repeats identically every ~38 seconds, indefinitely. Full trace log available if useful.

Let me know if there's anything else I can check in the meantime and have a great day

[dca31]

Hi,
Sunology have not been able to clarify exactly which model the inverter is but have narrowed it down to TSOL-MX400/MX450 or MX500.
Txs

[s-allius]

So these three inverters properly use the same hardware and the special type depends only on the configuration.

Do you see the inverter in a TSUN or solar man App?

[dca31]

Hi, I was able to create the device in the TSUN app as a "Hybrid micro inverter" using the Monitoring Serial Number, and it correctly pulled up the inverter serial number. So it's definitely reporting via the TSUN protocol, not Solarman.

Let me know if there's anything else useful I can check from the TSUN app now that the device is registered there (firmware version, model name, etc.).

Txs in advance

[dca31]

I have also left the inverter registered and active in the TSUN app for a while, then restarted the proxy - exact same behavior as before (connects, sends the sensor-list test, gets silence, peer closes after ~28s, repeats indefinitely). So cloud pairing doesn't seem to change anything for the local client_mode connection.

Still no luck finding the exact model name/firmware version in the TSUN app either.

[s-allius]

As I know, it is imporant, that your inverter have a direkt connection to the tsun cloud. There might be some special packets for completing the registration.
If you have enabled the forwarding in the proxy, it might not work, because the proxy is not able to create the proper packets for completing the registration.

Do you have a direkt connection from the inverter to the TSUN cloud? Is the forwarding in the proxy is disabled or the proxy complete disabled?

---

The TSUN App and Solarman use the same protocol for all inverters with a 'Yxx' serial-number. But if you have a OEM device, it might not work in every application

[dca31]

• I've never been able to access the inverter's local web-config page, so I never redirected its target IP away from the TSUN cloud or touched DNS either. So as far as I know, the inverter's normal/direct connection to the TSUN cloud should be completely untouched and still active.

• Forwarding in the proxy is currently disabled (False in the config, confirmed in the logs).

• The TSUN-proxy add-on is enabled and running normally

• My device is a Sunology PLAY2 kit, which is probably an OEM/rebranded product (Sunology is the reseller, TSUN makes the actual hardware). Does this mean that there is no further fix?

Happy to keep testing if there's anything else useful I can try.
Txs a lot

[s-allius]

• Ok, your inverter is running fine and you have the official software of Sunology running where you get some measurements, right?
• The inverter has an open port 8899, but we don't know the protcol. Maybe we have to send a magic sequence, or ...

---

I would open the port 8899 with a TCP terminal program and wait for any data on this connection. If there is something replayed from the internal connection, you will see some wild characters in the terminal program.

Then start a Whireshark and make a tcp trace on port 8899. if some binary data is sent over port 8899 we can see it in the Wireshark trace and can have a look if there is a well known pattern.

---

I think this is the only way. If there is no data on the port 8899, then this is properly disabled in the OEM firmware and we can't get any access.

[s-allius]

Important for Wireshark: you must trace in your router or between you access point and router. Maybe you have to setup a mirror port on a switch. If you make a Wireshark trace on your laptop you only see the traffic between your Laptop and your router, but not he traffic between your inverter and the router.

[s-allius]

I changed the headline of this thread, so we hopefully find other users of Sunology PLAY2 kit...

[dca31]

-The official Sunology app (Stream) shows measurements normally so the inverter itself is working fine.

• Tried the raw TCP terminal test with PuTTY (raw mode, port 8899, proxy stopped beforehand to avoid conflicts): the connection opens, but after about 30 seconds it closes on its own with no data received at all. Same ~30s timeout as what the proxy was seeing.

• Do you think it's still worth moving on to the Wireshark capture?