Legacy SolarEdge SE3500 LCD inverter — CPU 2.1049, no Modbus TCP menu or open ports

[MaciekZyga]

Hello,

I'm trying to integrate an older SolarEdge SE3500 inverter into Home Assistant for local monitoring and future energy-based automations.

Inverter details

• Model: SolarEdge SE3500-ER-01
• CPU firmware: 0002.1049
• DSP1/2: 1.0210 / 2.0052
• Country setting: GBR2
• Inverter IP: 192.168.0.72
• Ethernet connection to my local network

Tests performed

• The inverter responds to ping from my Ubuntu server with 0% packet loss.
• TCP ports 502, 80, 443 and 2222 all return “Connection refused”.
• In the inverter communication menu I can see Server <LAN>, RS485-1 Conf <S>, ZigBee Conf <N/A>, Wi-Fi Conf <N/A> and GPIO Conf <RRCR>.
• I have not found a Modbus TCP enable setting in the menus I can access.

Questions

1. Does CPU firmware 2.1049 support local Modbus TCP on this SE3500 model?
2. Is there a known firmware version that enables Modbus TCP, and can this inverter be safely upgraded to it?
3. Is there another menu path or installer-level setting that enables Modbus TCP on this hardware?
4. If Ethernet Modbus TCP is not supported, can I retrieve inverter data through RS485-1 instead? Which protocol and hardware interface would you recommend?
5. Is individual optimizer/module-level data available locally on this generation?

I want to begin with read-only monitoring and avoid changing power-control or grid settings.

Any advice or experience with this specific generation would be greatly appreciated.

Thank you.
Maciek

[salvadorbs]

Have you enabled Modbus in the inverter settings?

[Robert-2669]

I had a SE8K LCD Inverter with V2.x firmware. It does not support ModBus/TCP as you need V3.x for that.

Regarding the SolarEdge documentation on SunSpec supported inverters:

Depending on their type, SolarEdge devices may be configured in either of the two ways:

• Using SolarEdge Go mobile application
• Using the LCD

All SolarEdge inverters with SolarEdge Go configuration are SunSpec-supported.
SolarEdge inverters with the LCD that have Firmware version 3.xxxx and above only are SunSpecsupported.

Hint: As many people are swapping their older inverter for one with battery, my installer had a lot older inverters. I got a 4y old SE5K with V4.x for free from them. Works like a charm!