Sungrow SG320HX-20

Compatibility

Modbus monitoring route documented; Edge setup to check on site

Sungrow documents the RS485_1 monitoring chain and transparent Modbus RTU through its optional PLC logger. TESVOLT lists the exact SG320HX-20 for Modbus RTU and TCP in its energy-manager compatibility table. This is a practical third-party monitoring precedent, while the installed endpoint and Edge behaviour have not been tested here.

Use the SG320HX-20 English manual Ver13 (October 2024) and global datasheet V8 (January 2025) as the starting documents. Note the installed logger and firmware, then compare a first read with iSolarCloud. SG320HX without the -20 suffix is a separate generation.

Models

Specifications

The -20 suffix identifies a different PV input design. Datasheet V8 specifies six MPPTs with 75 A each, while the older SG320HX V17 datasheet specifies 12 MPPTs with an optional 16-input configuration. Select by the exact nameplate and document revision.^2, 3

PV voltage

1500 V maximum; 500–1500 V MPPT range; 550 V startup²

PV inputs

Six MPPTs, up to five input connectors each; 75 A maximum input current per MPPT²

AC output

352 kVA at 30°C; 320 kVA at 40°C; 300 kVA at 51°C²

AC connection

800 V nominal, three-phase with protective earth; 640–920 V range²

Efficiency

99.02% maximum; 98.8% European efficiency²

Monitoring

RS485_1 monitoring daisy chain or PLC through a Sungrow data logger¹

Third-party precedent

TESVOLT Energy Manager lists SG320HX-20 for Modbus RTU/TCP; endpoint and firmware scope require site confirmation⁵

Tracker communications

Separate RS485_2 on COM1 pins 7 and 8¹

Enclosure and environment

IP66; -30 to +60°C; forced air cooling; 5000 m maximum, derating above 4000 m²

Dimensions and weight

1148 × 779 × 371 mm; ≤106 kg, with manufacturer-stated ±8% component variation²

Interface

Documented measurements and integration boundaries for SG320HX-20.

• The iSolarCloud local interface shows string voltage and current, MPPT voltage and current, DC power, AC active/reactive/apparent power, line voltage, phase current and grid frequency.
• Operating information includes temperature, insulation resistance, yield and fault/event records. These are documented app functions; their external register addresses, scaling and update intervals are not supplied here.
• Inverter production, a site meter and tracker data serve different purposes. A displayed inverter yield does not establish revenue-meter accuracy or whole-site import and export.
• TESVOLT's exact-model listing supports a read-only Modbus trial over the installed RS485 or logger route. Use Sungrow's point list for the site's monitoring setup; the TESVOLT table is a compatibility list, not a register map.

Setup

1. Record the complete nameplate, regional configuration, installed firmware and logger identity.

   Match the six-MPPT SG320HX-20 documentation before designing either the PV strings or communications.

2. Use COM1 RS485_1 for the documented monitoring daisy chain: pins 1 and 2 are A1 positive, pins 3 and 4 are B1 negative, and pins 5 and 6 are shield protective earth.

   Refer to manual section 5.9 for the connector drawing and installation procedure.

3. Keep RS485_2 in its tracking-system role: pin 7 is A2 positive and pin 8 is B2 negative.

   It is not a spare monitoring port. Existing logger ownership must be resolved before any additional bus controller is connected.

4. The manual limits the RS485 cable to 1000 m and delegates the number of daisy chains and connected devices to the selected logger manual.

   Record the actual address and baud rate: section 7.8.4 offers addresses 1–246 and 9600, 19200, 38400, 57600 or 115200 bit/s; it does not establish parity, a register map or safe polling capacity.

5. For PLC, the inverter communicates over its AC output cables with a Sungrow data logger.

   Section 5.10 illustrates an MPLC node inside Logger4000 and refers wiring design to the logger manual. PLC is power line communication, not an Ethernet port or an industrial programmable controller.

6. Use the published third-party compatibility as a starting point: scope a read-only Modbus RTU trial at the commissioned RS485_1 monitoring chain or the logger's transparent RS485 output.

   Do not add a second bus master to an occupied chain. TESVOLT also lists TCP, but identify the installed logger or gateway that provides it rather than assuming an Ethernet server in the inverter.

7. Use a Sungrow SG320HX-20 register table as the starting point, noting its revision and address base.

   Read one state and one power value, compare them with fresh iSolarCloud readings and record the answering device. If they differ, check the installed firmware, logger mapping and scaling before adding points. Active/reactive-power settings, grid functions, boot/shutdown and firmware updates need a separate authorised commissioning procedure.

8. Change the initial local app password and restrict physical and network access to the inverter and logger.

   The app account model does not establish authentication or encryption for an external RS485 connection.

Common questions

Is SG320HX-20 the same as SG320HX?

No. The -20 datasheet specifies six MPPTs and up to 30 DC inputs. The older SG320HX has 12 MPPTs with an optional 16-MPPT configuration, different current limits and different enclosure dimensions. Use the full model suffix for equipment and protocol selection.^2, 3

Does the inverter provide Modbus TCP?

TESVOLT lists SG320HX-20 with Modbus TCP and RTU in its Energy Manager compatibility table. Sungrow's manual confirms transparent RTU at the optional PLC logger; neither source identifies a native TCP server in the inverter. For a TCP project, identify the installed logger or gateway and obtain its endpoint, firmware and register contract.^1, 5

Can the tracker port be used for an additional monitoring connection?

COM1 RS485_2 is assigned to tracking-system communications. The monitoring daisy chain uses RS485_1. Confirm the permitted topology with Sungrow before adding another controller.¹