SUN2000 Modbus Register Map: V2 and V3

Complete Modbus register reference for Huawei SUN2000 inverters: system info, DC, AC, energy, temperature, and inverter state decode table.

The SUN2000 register map is organized into functional groups. You read all registers with FC 03 (Read Holding Registers). INT32 and UINT32 values span two consecutive registers — always request both in a single transaction to guarantee consistency. Divide each raw integer by its gain to obtain the real physical value.

Register addresses differ between SUN2000 series (L0, L1, M0, M1, M2, M3, MA, MB0). The addresses below match the SUN2000MA and SUN2000-M1/M3 Modbus Interface Definitions (Issue 08, 2024-11-07). Verify every address against the Modbus Interface Definitions for your specific model before deploying to production.

System information registers (read-only)

Register	Description	Type	Gain
30000	Inverter model	String	—
30015	Serial number (SN)	String	—
32089	Run state	U16	1

Register 32089 returns one of the coded integers in the state decode table below.

DC side registers (solar panels)

Register	Description	Type	Gain	Unit
32016	PV1 voltage	I16	10	V
32017	PV1 current	I16	100	A
32064	DC input power	I32	1	W

AC side registers (grid)

Register	Description	Type	Gain	Unit
32066	Line voltage L1-L2 (AB)	U16	10	V
32069	Phase voltage A (L1-N)	U16	10	V
32070	Phase voltage B (L2-N)	U16	10	V
32071	Phase voltage C (L3-N)	U16	10	V
32072	Phase A current	I16	10	A
32074	Phase B current	I16	10	A
32076	Phase C current	I16	10	A
32078	Reactive power	I32	1	var
32080	Active power	I32	1	W
32082	Power factor	I16	1000	—
32085	Grid frequency	U16	100	Hz

Register 32080 (Active power) is signed: positive values indicate generation, negative values indicate consumption from the grid.

Energy and temperature registers

Register	Description	Type	Gain	Unit
32106	Daily yield	U32	100	kWh
32109	Total yield	U32	100	kWh
32087	Internal temperature	I16	10	°C

Inverter state decode (register 32089)

Raw value	State
0	Idle: Initializing
1	Idle: Detecting ISO
2	Idle: Detecting irradiation
3	Idle: Grid Detecting
256	Starting
512	On-Grid (normal operation)
513	On-Grid: Power Limit
514	On-Grid: Self-derating
768	Shutdown: Fault
769	Shutdown: Command
770	Shutdown: OVGR
771	Shutdown: Comm. disconnected
772	Shutdown: Power Limit
1280	Spot-check
2048	IV Scanning
40960	Idle: No irradiation

Top 10 registers for Home Assistant, Node-RED, and SCADA

These registers cover the most common monitoring requirements with minimal polling overhead:

Register	Parameter	Type	Gain	Notes
32064	DC input power	I32	1	Total power from panels (W)
32069	Phase voltage A (L1-N)	U16	10
32070	Phase voltage B (L2-N)	U16	10
32071	Phase voltage C (L3-N)	U16	10
32080	Active power AC	I32	1	positive = generation, negative = consumption
32085	Grid frequency	U16	100
32087	Internal temperature	I16	10	°C
32089	Inverter run state	U16	1	512 = On-Grid
32106	Daily yield	U32	100	kWh
32109	Total yield	U32	100	kWh

Python example: reading key registers

The example below uses the pymodbus library to connect over Modbus TCP and read a selection of the registers above.

from pymodbus.client import ModbusTcpClient
from pymodbus.constants import Endian
from pymodbus.payload import BinaryPayloadDecoder

HOST = "192.168.200.1"  # Inverter Wi-Fi AP address
PORT = 6607             # New-firmware SDongle port; use 502 for old firmware
SLAVE_ID = 1

client = ModbusTcpClient(HOST, port=PORT)
client.connect()

def read_u16(address):
    result = client.read_holding_registers(address, count=1, slave=SLAVE_ID)
    return result.registers[0]

def read_i16(address):
    raw = read_u16(address)
    return raw if raw < 0x8000 else raw - 0x10000

def read_i32(address):
    result = client.read_holding_registers(address, count=2, slave=SLAVE_ID)
    decoder = BinaryPayloadDecoder.fromRegisters(
        result.registers, byteorder=Endian.BIG, wordorder=Endian.BIG
    )
    return decoder.decode_32bit_int()

def read_u32(address):
    result = client.read_holding_registers(address, count=2, slave=SLAVE_ID)
    decoder = BinaryPayloadDecoder.fromRegisters(
        result.registers, byteorder=Endian.BIG, wordorder=Endian.BIG
    )
    return decoder.decode_32bit_uint()

# DC side
dc_power_w    = read_i32(32064)

# AC side
phase_a_v     = read_u16(32069) / 10   # Volts
active_power_w = read_i32(32080)        # W, positive = generation
grid_freq_hz  = read_u16(32085) / 100  # Hz
temperature_c = read_i16(32087) / 10   # °C
run_state     = read_u16(32089)

# Energy
daily_kwh     = read_u32(32106) / 100
total_kwh     = read_u32(32109) / 100

print(f"DC input power : {dc_power_w} W")
print(f"Phase A voltage: {phase_a_v} V")
print(f"Active power   : {active_power_w} W")
print(f"Grid frequency : {grid_freq_hz} Hz")
print(f"Temperature    : {temperature_c} °C")
print(f"Run state      : {run_state}  (512 = On-Grid)")
print(f"Daily yield    : {daily_kwh} kWh")
print(f"Total yield    : {total_kwh} kWh")

client.close()