Client mode: inverter connects but never responds to sensor-list test (Y47 prefix, HA Green)

[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?