Sungrow SG15/17/20RT-P2

Three-phase PV string inverter

The SG15RT-P2, SG17RT-P2 and SG20RT-P2 share Sungrow's two-MPPT three-phase design. The Ver16 manual assigns COM2 A1/B1 to external RS-485 communication and A2/B2 to the export-control meter. It prohibits simultaneous A1/B1 daisy-chain use with the COM1 WiNet module. No exact-family, firmware-matched third-party register map is established here, so a direct Edge monitoring or control path remains unverified.

Sungrow SG15/17/20RT-P2 three-phase PV inverter
  • RS485

Three-phase PV string inverter

Compatibility

Independent monitoring needs an exact register contract

The Sungrow Ver16 manual documents COM2 A1/B1 RS-485 communication to an external device and a daisy chain, but the retained manual and datasheet do not provide an SG15/17/20RT-P2 firmware-matched register map, read permissions or an Edge import. WiNet Ethernet does not establish a native Modbus TCP server.

SG15RT-P2, SG17RT-P2 and SG20RT-P2 only. Confirm the full nameplate, firmware, regional grid code, fitted WiNet module, logger and meter. COM2 A1/B1 cannot be used simultaneously with the documented COM1 WiNet setup. Older RT models without -P2 and SG15/20/25CX-P2 are different products.

Models

Download
ModelsInterfaceRoute into Edge
SG15RT-P2, SG17RT-P2 and SG20RT-P2COM2 RS485-1 A1/B1 for external-device or inverter daisy-chain communication; meter A2/B2 is a different pairIdentify the existing COM1 WiNet and logger arrangement before considering any independent serial client. Obtain a matching inverter or logger read protocol first.
SG3.0-20RT without -P2The shared Ver16 manual covers these older RT models too, but distinguishes their WiNet-S2 accessory from the P2 WiNet-S arrangementDo not infer that connector or firmware assumptions from the non-P2 models apply to an installed P2 unit.

Specifications

The exact-family V2 datasheet names SG15RT-P2, SG17RT-P2 and SG20RT-P2 with 15, 17 and 20 kW rated AC output, two MPPTs, two strings per MPPT and 22 kg enclosure weight. The newer Ver16 manual is the source for regional apparent-power limits and the COM connector roles. A shared housing does not make non-P2 or CX-P2 guides interchangeable.12

Exact models
SG15RT-P2, SG17RT-P2 and SG20RT-P212
Rated AC output
15, 17 and 20 kW respectively12
PV inputs
Two MPPTs; two strings per MPPT; 1100 V maximum PV input2
PV input current
64 A total, 32 A per MPPT; 80 A maximum short-circuit current total2
Regional AC maximum
15/17/20 kVA for AU, BE and DE; 16.5/18.7/22 kVA for other manual configurations1
COM2 monitoring pair
RS485-1 A1/B1 for inverter daisy chain or external device; not simultaneous with COM1 WiNet1
COM2 meter pair
A2/B2 for feed-in power meter; A3/B3 reserved1
RS-485 chain boundary
No more than five inverters at one point of connection; shielded twisted pair, up to 10 m between devices1
Enclosure
370 × 480 × 195 mm, 22 kg, IP652

Interface

Documented measurements and integration boundaries for SG15/17/20RT-P2.

  • COM2 A1/B1 is the documented RS-485 daisy-chain pair. The manual limits a chain at one point of connection to five inverters and specifies shielded twisted pair with no more than 10 m between devices; a logger's own limits still need checking.
  • COM2 A2/B2 is assigned to the feed-in power meter and A3/B3 is reserved. The meter detects current direction and magnitude; Sungrow says its data may not be used for billing. Neither pair is a spare third-party telemetry port.
  • The manufacturer describes 24/7 online monitoring and an integrated display, but these do not establish an external register address, scale, update interval or native inverter Ethernet service.
  • Regional AC apparent-power limits differ. The Ver16 manual gives 15/17/20 kVA maximum for AU, BE and DE, versus 16.5/18.7/22 kVA in other listed configurations. Verify the nameplate and grid setting before sizing or comparing output.
  • DRM and emergency-stop terminals are control and safety functions. This guide does not authorize inverter write commands, export-limit changes or demand-response actuation.

Assessment

SG15RT-P2, SG17RT-P2 and SG20RT-P2, Ver16 manual and V2 datasheet. No firmware-matched external read map, Edge integration or control acceptance is claimed.

InteroperabilityLimited
An external-device RS-485 pair is documented, but WiNet coexistence is restricted and no exact-family third-party read map is retained.1
AccuracyLimited
Display and online monitoring exist, yet independent register scaling, freshness and grid-meter provenance are not established by these sources.12
SecurityNot yet assessed
The manual describes communication wiring but does not establish authentication or encryption for an independent RS-485 client.1
ReliabilityNot yet assessed
Online monitoring is advertised, but no third-party polling availability or historical backfill guarantee is established.12
RuggednessSupported with conditions
The datasheet specifies IP65, C5 anti-corrosion and the ambient range. Suitability still depends on the exact site installation and regional derating.12
ScalabilityLimited
The manual permits at most five daisy-chained inverters at one point of connection and 10 m between devices; an external polling capacity is not documented.1
LifecycleSupported with conditions
Sungrow publishes an exact-family datasheet and a later Ver16 manual. Keep the installed firmware, accessory and grid-code revision with the integration record.123

Setup

  1. Read the complete installed nameplate and firmware.

    Confirm SG15RT-P2, SG17RT-P2 or SG20RT-P2, the country setting, existing meter, COM1 WiNet module and any logger before choosing a telemetry path.

  2. Trace COM2 wiring: A1/B1 is the inverter communication pair, A2/B2 belongs to the feed-in meter and A3/B3 is reserved.

    Do not move the meter or use the reserved pair for a monitoring client.

  3. If COM1 WiNet is fitted, preserve the manufacturer's exclusion of simultaneous WiNet and A1/B1 daisy-chain communication.

    Agree any change with the plant owner and Sungrow installer before altering network or serial wiring.

  4. Request the manufacturer-approved protocol for the installed inverter or logger and firmware: function codes, read permissions, address base, widths, word order, scaling, exception values and polling interval.

    The retained sources do not establish these items.

  5. Only after that contract and bus ownership are confirmed should an installer perform a bounded read and compare it with the inverter display and an independently identified grid meter.

    Document timestamps, stale-data behaviour and the actual measurement boundary.

  6. Keep grid-code, export-limit, power-factor, DRM, emergency-stop, start/stop and firmware operations under the authorized plant controls.

    A VPP dispatch route needs a separate control and acceptance design.

Sources

  1. SG3.0-20RT and SG5.0-20RT-P2 user manual, Ver16, October 2025 (opens in a new tab) (PDF) Sungrow
  2. SG15/17/20RT-P2 datasheet, V2 (opens in a new tab) (PDF) Sungrow
  3. SG15/17/20RT-P2 official product page (opens in a new tab) Sungrow

Further reading

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