Is the Solis S-GR3P S5-GR3P5K compatible with the Solis Eastron SDM230-Modbus (1ph)?

Yes — listed by the manufacturer.

The manufacturer's published pairing data lists these together.

Manufacturer's compatibility listListed together in the manufacturer's published pairing data. A cited document reference is being added as datasheets are processed.

Pairing details

Both products

Design a system with this pair