Read Growatt without the cloud: SPH locally via RS485 or OpenInverterGateway

Which Growatt devices work locally?

Locally SUNA reads the SPH hybrid inverter with battery: single-phase SPH 3000 to 6000TL BL‑UP, three-phase SPH 4000 to 10000TL3 BH‑UP. The MIN and TL‑XH string inverters only work via the cloud with SUNA Online so far.

The two ways compared

• RS485 gateway: a small device for about 30 to 40 € on the RS485 interface of the inverter, connected to the router by cable. The simplest way, but still beta in SUNA.
• OpenInverterGateway: the Growatt USB stick gets a free firmware instead of the Growatt one and sends its values to an MQTT broker on your home network. Stable in SUNA, but something for tinkerers.
• Either way new values arrive about every 10 seconds, even without internet.

Way 1: RS485 gateway

1. On the inverter set the RS485 port to “VPP” and the RS485 address to 1, in the menu on the device or with the installer tool. According to user reports the port delivers no data otherwise. Older devices without “UP” in the name may need a firmware update.
2. Connect the gateway to the RS485 port meant for monitoring (A, B and ground). Which one that is, is in the manual. Do not use the meter or battery port, two masters on one bus disturb each other. If nothing arrives, swap A and B first.
3. Set up the gateway: 9600 baud, 8 data bits, no parity, 1 stop bit (8N1), mode “Modbus TCP to RTU”, TCP server on port 502, fixed IP address in the router.
4. In SUNA Home under Setup, Inverter choose “Growatt SPH (Modbus)”, enter the IP address of the gateway, port 502 and Modbus address 1, and start. After about 10 seconds it should say that data is arriving.

Way 2: OpenInverterGateway

1. Flash the free OpenInverterGateway firmware onto the Growatt USB stick. The project on GitHub describes how.
2. Run an MQTT broker on your home network, for example Mosquitto, and let the stick send its values there.
3. In SUNA Home under Setup, Inverter choose “Growatt SPH (OpenInverterGateway)”, enter the broker address (for example mqtt://192.168.178.20:1883), user, password and the topic of the stick. By default the topic is energy/solar.

Why does SUNA show a different home consumption?

SUNA calculates home consumption without the inverter losses. It is therefore often a little lower than in the Growatt app, but more accurate.

No tinkering: via the cloud

Rather not connect anything? SUNA Online shows SPH, MIN and TL‑XH via the Growatt cloud. You create the API token yourself in the ShinePhone app, there is nothing to apply for. New values then arrive about every 5 minutes.