An online Solis datalogger—whether connected to Wi-Fi or visible in SolisCloud—is not proof that a local Modbus TCP interface is available. Check the model number on the logger itself before commissioning.
| Solis datalogger | Connector | Local Modbus TCP | Controllerion |
|---|---|---|---|
| S2-WL-ST | 4-pin | ✅ Port 502 | Compatible and verified in the field |
| S3-WIFI-ST | 4-pin | ❌ Not available | Not compatible with the Modbus TCP connection described on this page |
The S2-WL-ST is a Wi-Fi/LAN logger that officially supports Modbus TCP. Solis also provides a Modbus TCP setup guide for the S2-WL-ST. The S3-WIFI-ST is a Wi-Fi-only logger: it can send data to SolisCloud, but it does not expose the local Modbus TCP server required by the EMS.
If an S3-WIFI-ST is installed, replace it with an S2-WL-ST (4-pin) before using Modbus TCP, or connect the inverter directly through RS485 when that is suitable for the installation.
If the logger is online in SolisCloud but port 502 times out, verify the logger model first. Changing the inverter address or repeating a scan will not make an S3-WIFI-ST provide Modbus TCP.
| Device Type | Modbus TCP (Ethernet) | RS485 | Curtailment |
|---|---|---|---|
| S5-GR3P(3-20)K | ✅ with compatible logger | ✅ | ✅ |
| S5-GC(25-40)K | |||
| S5-GC(50-60)K | |||
| S5-GC80K | |||
| S5-GC(100-110)K | |||
| S6-GR1P(0.7-3.6)K-M | |||
| S6-GR1P(2.5-6)K | |||
| S6-GR1P(7-8)K02-NV-YD-HC | |||
| S6-GC3P(40-60)K-NV-ND | |||
| S6-GC(80-125)K | |||
| S6-GC3P150K07-NV-ND | |||
| S6-GU350K-EHV | |||
| 100-125K G5 | experimental | ||
| Solis-80K-5G-PRO | ✅ with compatible logger | ||
| Solis-255K-EHV-5G-PLUS |
| Model | Page |
|---|---|
| S5-GR3P(3-20)K | Wiring configuration for S5/S6 Series |
| S5-GC(25-40)K | |
| S5-GC(50-60)K | |
| S5-GC80K | |
| S5-GC(100-110)K | |
| S6-GR1P(0.7-3.6)K-M | |
| S6-GR1P(2.5-6)K | |
| S6-GR1P(7-8)K02-NV-YD-HC | |
| S6-GC3P(40-60)K-NV-ND | |
| S6-GU350K-EHV | |
| 100-125K G5 | Wiring configuration for Industrial PV installation |
| Solis-80K-5G-PRO | |
| Solis-255K-EHV-5G-PLUS |
By default, the inverter is set to address 1. This can be changed via the display of the inverter. You can find the procedure in chapter 7.3.2 of the manual.