Growatt MAX 320K/333K/350K-X

Compatibility

Direct Edge integration not yet verified

Growatt documents RS485-1 inverter/data-logger wiring, optional PLC/Wi-Fi/4G monitoring and a ShineMaster topology. The retained MAX 300–350K-X manual does not assign an external meter role to its RS485-2 pins or provide a third-party read register map, function codes, TCP endpoint, permissions or writes for these installed models.

Identify the exact 320K-X, 333K-X or 350K-X nameplate, country approval, 800 V AC/transformer design, firmware, ShineMaster or PLC hardware and grid-point meter. Ask Growatt for the matching external read contract. Keep power factor, active-power limits, DRM and utility dispatch with the commissioned controller and grid operator.

Models

Specifications

The September 2026 source sheet lists 320K-X, 333K-X and 350K-X at nominal 320, 333 and 352 kW AC respectively, with 800 V AC, six MPPTs, five strings per MPPT, 80 A maximum input current per tracker, IP66 and optional GPRS/4G/Wi-Fi communications. It is a raster PDF; the exact table was visually reviewed rather than inferred from extracted text.²

Covered models

MAX 320K-X, MAX 333K-X and MAX 350K-X^2, 3

Nominal AC power

320, 333 and 352 kW respectively; 800 V AC, 3W+PE²

PV tracking

Six MPPTs, five strings each, 80 A maximum input per tracker²

MPPT range discrepancy

September sheet: 500–1500 V; June manual: 800–1330 V. Confirm applicable hardware revision before design^2, 3

RS485-1 network

COM pins 3/4 A1/B1 input and 5/6 A1/B1 output; terminal resistor option on 15/16³

RS485-2

COM pins 7/8 listed; external meter or third-party role not defined in retained manual³

Optional monitoring

PLC, Wi-Fi and 4G; exact hardware and external access require site verification^1, 3

Enclosure

IP66, smart air cooling, 139 kg; altitude derating above 4000 m²

Interface

Documented measurements and integration boundaries for MAX 320K/333K/350K-X.

• The June 2026 manual assigns the COM port's RS485-1 input to pins 3/4 (A1/B1) and output to 5/6 (A1/B1). It says single-inverter communication can use 3/4 and a multi-inverter run can use both sets. Pins 15/16 enable matching resistance on the last inverter. Check the actual connector type, as Growatt says two appearance variants ship.
• The manual describes up to 32 inverters, 500 m and 38400 baud on its RS485 COM network. This is an inverter-bus design limit, not proof of a third-party polling capacity. Its ShineMaster diagram connects the logger to RS485-1 and uploads plant data to Growatt's server.
• RS485-2 pins 7/8 are shown in the COM table, but the retained manual does not state that they are a grid meter, northbound Edge interface or safe second-master port. Growatt also says its monitoring smart meter and environmental monitor must be designated models. Trace the actual site topology and obtain the model-specific function document.
• The product page calls PLC communication optional, while the manual lists optional PLC, Wi-Fi and 4G monitoring. These are alternative site equipment choices; neither establishes a local HPLC protocol, Ethernet Modbus TCP endpoint or authorisation to bypass the Growatt logger.
• The September 2026 datasheet gives a 500–1500 V MPPT range, while the June manual lists 800–1330 V. Both list 1500 V maximum DC input, which is a separate absolute limit. Engineering selection needs Growatt's revision-specific clarification and the installed nameplate; neither range should be silently selected.
• This is an 800 V three-wire plus PE, transformerless inverter for an IT-connected grid arrangement in the manual. The transformer, medium-voltage connection, grid-point revenue meter and plant controller must be assessed separately before claiming site export or dispatch capacity.

Setup

1. Identify the utility-voltage inverter

   Record the exact 320K-X, 333K-X or 350K-X nameplate, firmware, country approval and 800 V AC switchgear/transformer arrangement. Do not reuse a 400 V MAX family design.

2. Resolve the DC design discrepancy

   Ask Growatt which MPPT operating range applies to the installed hardware and firmware. The later sheet states 500–1500 V and the manual states 800–1330 V, while 1500 V maximum input is a separate limit.

3. Trace the monitoring owner

   Identify ShineMaster, optional PLC, Wi-Fi or 4G equipment, existing RS485 addresses and COM termination. Keep Growatt's designated meter and environmental equipment distinct from the inverter's own telemetry.

4. Request a bounded read contract

   Obtain the exact firmware and logger-matched third-party point map, function, address convention, scaling, units, timestamp behaviour and polling limits. Test one read against Growatt's own view with the operator present.

5. Qualify site flexibility separately

   Use a trusted grid-point meter and approved controller to establish net import/export, transformer limits, curtailment rights, reactive duty and fail-safe behaviour. Do not send inverter writes from this selection guide.

Common questions

Is MAX 350K-X exactly a 350 kW nameplate?

The September 2026 model table calls it MAX 350K-X but lists 352,000 W nominal AC power. Confirm the site-specific approval and thermal schedule rather than interpreting the marketing code as the exact rating.²

Which MPPT operating range is correct?

The current September sheet says 500–1500 V; the linked June manual says 800–1330 V. Both cite 1500 V maximum input. Treat the operating range as unresolved until Growatt identifies the applicable hardware and firmware revision.^2, 3

Is RS485-2 the grid meter or an Edge port?

The manual lists RS485-2 pins 7/8 but does not assign either a grid-meter or third-party Edge role to them. Growatt's designated meter requirement and installed site wiring must be checked before making that claim.³

Does optional PLC mean direct HPLC or Modbus TCP integration?

No direct endpoint is established in these documents. The product page advertises optional PLC and the manual lists monitoring via RS485, PLC, Wi-Fi or 4G. Identify the actual Growatt module, logger and its authorised external interface before choosing a protocol.^1, 3