Discovery

The droplet discovers the inverters behind the logger but not the logger itself.

At the moment SwitchDin is not integrating directly with the Sungrow Data logger itself. This device will not be listed in the 'Discovery' process if you try to add this device in Stormcloud application.
We are just using it as a proxy to get to the PV inverter devices behind it.

Connection and Wiring

Effectively the logger is just acting as a modbus RTU to TCP translator.

The connection from the droplet to the logger is TCP (You will need a Cat6 cable).
From the logger to the inverters the connection is RS485.

The devices behind the logger appear on their regular slave ids, e.g. 1,2,3 and the loggers memory map appears on slave 247.

Enabling Droplet controls to your inverters

The Sungrow Logger has the ability to control the inverters behind it.

When it’s connected to the droplet the droplet controls the devices behind by sending control commands to the inverters, not to the logger.

So you need to turn off the Logger's control, otherwise it will periodically send control commands to the devices which interfere with the droplet controls, e.g. turning off the power control limit switch (i.e. disabling pv limit control) which causes the droplet to run out of the limited number of writes to this register as it is in EEPROM.

The loggers control function can be disabled through its web interface, login with password 1111 and navigate to: Power Control -> Active Power -> Active Control Mode -> Disable Dispatching