Huawei SUN2000 (Modbus RTU)

Modbus RTU

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Last updated: 03. 2026

Huawei FusionSolar

The Huawei SUN2000 3-10KTL series are three-phase string inverters for residential PV systems, with rated power from 3 kW to 10 kW. This template connects to the inverter via Modbus RTU over RS-485, using the COM port on the bottom of the inverter. Unlike the TCP variant (which uses a Smart Dongle for network connectivity), the RTU variant communicates directly over a serial RS-485 bus.

The template provides active power monitoring with power control actions, DC input power with grid-side measurements, PV string current and voltage readings, grid power meter (via Smart Power Sensor), battery state of charge, daily and cumulative energy counters, and detailed inverter status with alarm decoding.

Huawei warns that Modbus RTU communication may become unstable when the inverter communicates with cloud servers via the WLAN Smart Dongle. Disconnect the WLAN Smart Dongle before using Modbus RTU to avoid CRC errors and communication failures on the RS-485 bus.

Hardware connection

The SUN2000 inverter has a 16-pin COM port (#8) on the bottom panel. The COM port provides two separate RS-485 buses:

Bus	Pins	Purpose
Bus 1	Pin 1 (485A1-1), Pin 3 (485B1-1)	Cascading inverters, SmartLogger, TapHome connection
Bus 2	Pin 7 (485A2), Pin 9 (485B2)	Smart Power Sensor, energy storage

For TapHome Modbus RTU connection, use Bus 1:

Pin 1 (485A1-1) – connect to RS-485 A+ on TapHome controller
Pin 3 (485B1-1) – connect to RS-485 B- on TapHome controller
Pin 5 (PE) – shield ground (optional but recommended)

Inverter port locations

SUN2000 inverter bottom panel showing COM port (#8) and Smart Dongle port (#9)

The COM port (#8) is located on the bottom panel, next to the AC output port (#7) and the Smart Dongle port (#9).

COM port pinout

SUN2000 COM port 16-pin connector with pin numbering

Pin	Definition	Function
1	485A1-1	RS-485 A+ (Bus 1) – connect to TapHome A+
2	485A1-2	RS-485 A+ (Bus 1) – for cascading to next inverter
3	485B1-1	RS-485 B- (Bus 1) – connect to TapHome B-
4	485B1-2	RS-485 B- (Bus 1) – for cascading to next inverter
5	PE	Shield layer grounding
7	485A2	RS-485 A+ (Bus 2) – Smart Power Sensor
9	485B2	RS-485 B- (Bus 2) – Smart Power Sensor

RS-485 cable installation

RS-485 signal cable installation into COM port connector showing pin positions 485A1-1, 485B1-1, and PE

Use an outdoor shielded twisted pair cable. Strip the outer jacket approximately 55 mm and the inner insulation 12-14 mm. Insert wires into the correct pin positions on the signal cable connector, then insert the connector into the COM port and turn clockwise to lock. Secure with the M3 screw (torque: 0.55 N.m).

Route the RS-485 signal cable separately from power cables to prevent electromagnetic interference.

Configuration

Communication parameters

Parameter	Value
Protocol	Modbus RTU
Baud rate	9600 bps
Data bits	8
Parity	None
Stop bits	1
Slave ID	1 (default, configurable via FusionSolar app)

Setting the Slave ID

The default Modbus slave address is 1. To change it:

Connect to the inverter via the FusionSolar app (initial WiFi password: Changeme)
Log in as installer (initial password: 00000a)
Navigate to communication settings and change the RS-485 address
Change the default password immediately after first login

The WLAN Smart Dongle must be disconnected for stable Modbus RTU communication. If the dongle is installed for FusionSolar cloud monitoring, remove it after configuration and before connecting TapHome via RS-485.

Device capabilities

The template exposes the following devices:

Active Power

An electricity meter device that reads the inverter’s current AC output power in kW (register H:32080, Int32, divided by 1000). This is the primary power monitoring device and provides both read and write capabilities.

Service attributes include peak active power of the day (H:32078), reactive power in kVar (H:32082), rated power, maximum active power, maximum apparent power, and maximum reactive power ratings (feed to grid and absorbed from grid).

Three service actions allow power control:

Reactive Power Compensation (PF) – set power factor from -1.0 to 1.0 (writes to H:40122)
Reactive Power Compensation (Q/S) – set reactive power ratio from -1.0 to 1.0 (writes to H:40123)
Active Power Derating (%) – limit output power as percentage 0-100% (writes to H:40125)

Battery

Displays battery state of charge as a percentage (register H:37760, UInt16, divided by 1000). A service attribute shows the battery running status (H:37762) with values: Offline, Standby, Running, Fault, or Sleep Mode.

The Battery device only appears functional when a LUNA2000 battery is connected to the inverter. Without a battery, the running status will show “Offline” and SOC will read zero.

Grid Power Meter

Reads active grid power from the Smart Power Sensor in kW (register H:37113, Int32, divided by 1000) and grid exported energy in kWh (register H:37119, Int32, divided by 100). Positive values indicate power exported to the grid, negative values indicate power imported from the grid.

Service attributes show the meter status (Normal/Offline) and meter type (3-phase/1-phase).

The Grid Power Meter device requires a Huawei Smart Power Sensor (DTSU666-H) connected to the inverter via RS-485 Bus 2 (pins 7 and 9 on the COM port). This device is not present in the TCP variant.

DC Input Power

Read-only sensor showing total DC power from all PV strings combined in kW (register H:32064, Int32, divided by 1000).

Service attributes provide grid-side measurements: grid frequency (H:32085), phase voltages A/B/C (H:32069-32071), phase currents A/B/C (H:32072-32076), and line-to-line voltages AB/BC/CA (H:32066-32068).

Daily Energy and Total Energy

Two read-only energy counters:

Daily Energy – energy generated today in kWh (register H:32114, divided by 100), resets daily
Total Energy – cumulative energy since commissioning in kWh (register H:32106, divided by 100)

PV string currents (PV1-PV2)

Two separate sensor devices, one per PV string, reading DC current in amps (registers H:32017 and H:32019, Int16, divided by 100). Each device includes a service attribute for the corresponding string voltage (H:32016 and H:32018, divided by 10).

The RTU template includes 2 PV string devices (PV1-PV2) compared to 4 in the TCP variant. The register map supports up to 24 strings – additional PV string devices can be added manually if needed.

Inverter Status

A multi-value switch (read-only) showing the inverter’s current operating state from register H:32089:

Value	State	Description
0	Inverter State	Initial / unknown
1	Idle	Detecting ISO, irradiation, or grid
2	Starting	Inverter starting up
3	On Grid	Normal power generation
4	Shutdown	Fault, command, OVGR, or DC switch off
5	Grid Dispatch	cos(Phi)-P or Q-U curve active
6	IV Scanning	PV string I-V curve scanning
7	Spot-Check	Grid spot-check in progress
8	Inspecting	Inspection mode
9	DC Input Detection	Detecting DC input

Service attributes provide detailed state information: Full State (expanded status with sub-states), Grid Connection status, Teleindication (IEC104 telesignaling), Locking Status, PV Connection Status, and Startup/Shutdown timestamps.

Alarm monitoring

The module-level read script monitors alarm registers H:32008 and H:32009 (Bitfield16). Each bit maps to a specific fault or warning:

Register	Bit	Alarm
H:32008	0	High String Voltage
H:32008	1	DC Arc Fault
H:32008	2	String Reversed
H:32008	3	Abnormal String (warning)
H:32008	7	Power Grid Failure
H:32008	8-9	Grid Under/Overvoltage
H:32008	11-13	Grid Frequency Faults
H:32008	14-15	Output Overcurrent / DC Component
H:32009	0	Abnormal Leakage Current
H:32009	1-2	Ground / Insulation Faults
H:32009	3-4	High Temperature / Equipment Fault
H:32009	9	Abnormal Energy Storage Device
H:32009	10-11	Active/Passive Islanding

Module-level diagnostics

The module exposes service attributes for device identification and diagnostics:

Attribute	Register	Description
Model Name	H:30000	Inverter nameplate model
SN	H:30015	Serial number
PN	H:30025	Product code
Model ID	H:30070	Numeric model identifier
Number of Strings	H:30071	Connected PV strings
MPPT Number	H:30072	MPP tracker count
Time Zone	H:43006	UTC offset
Inverter Efficiency	H:32086	Conversion efficiency (%)
Cabinet Temperature	H:32087	Internal temperature
Insulation Resistance	H:32088	PV array insulation
DSP Data Collection	H:32002	Data collection status

A Time Zone service action allows setting the inverter’s UTC offset (writes to H:43006).

Additional capabilities

The SUN2000 inverter exposes additional registers not yet implemented in the template. These include firmware version, fault code register, a faster-updating active power reading, total DC input energy counter, monthly and yearly energy counters, battery charge/discharge power, unsigned grid exported energy, grid accumulated energy, and remote power on/shutdown commands. These can be added in a future template update.

Differences from the TCP variant

The RTU template includes two devices not present in the TCP variant: the Grid Power Meter (Smart Power Sensor readings) and Battery with SOC readout. However, the RTU template only includes 2 PV string devices (PV1-PV2) compared to 4 in the TCP variant. The register map is identical – only the transport layer differs (RS-485 serial vs TCP/IP via Smart Dongle).

Troubleshooting

No Modbus communication

Verify the RS-485 cable is connected to the correct COM port pins: Pin 1 (485A1-1) = A+, Pin 3 (485B1-1) = B-
Ensure the WLAN Smart Dongle is disconnected from the inverter
Check that the baud rate is set to 9600 and parity to None (8N1) in TapHome
Confirm the correct Slave ID (default: 1)
Verify the signal cable connector is fully inserted and locked into the COM port

Intermittent communication failures

The most common cause is the WLAN Smart Dongle interfering with the RS-485 bus. The dongle’s internal communication with Huawei cloud servers causes CRC errors on the serial bus. Remove the dongle for stable RTU operation.

PV string values read zero

Unused PV string inputs will always read 0 A / 0 V. This is normal if the inverter model has fewer MPPT inputs than the template provides (e.g., a 3KTL model may only use PV1 and PV2).

Battery device shows “Offline”

The LUNA2000 battery registers are only populated when a compatible battery is physically connected to the inverter. Without a battery, Running Status will read “Offline” and SOC will be zero.

Inverter status stuck on “Idle”

During nighttime or low-irradiation conditions, the inverter enters idle mode. This is normal – it will transition to “On Grid” once sufficient solar irradiation is detected. The inverter may also have reduced data availability during standby.

Grid Power Meter reads zero

The Grid Power Meter device requires a Huawei Smart Power Sensor (DTSU666-H) connected via RS-485 Bus 2 (pins 7 and 9). If no meter is installed, the values will read zero and the meter status will show “Offline”.

Available devices

SUN2000 Module

Service Attributes

Model Name
SN
PN
Model ID
Number of Strings
MPPT Number
Time Zone	Inverter UTC offset — reads and displays the configured time zone
Inverter Efficiency	DC-to-AC conversion efficiency as percentage
Cabinet Temperature	Internal inverter enclosure temperature
Insulation Resistance	PV array insulation resistance in megaohms — monitors isolation safety
DSP Data Collection	Data collection status — Yes (active) or No (inactive)

Service Actions

Time Zone

Set the inverter UTC offset — select from UTC-12:00 through UTC+14:00

SUN2000

Read (module)

var a1 := MODBUSR(H, 32008, Uint16);
var a2 := MODBUSR(H, 32009, Uint16);
IF(GETBIT(a1,0) = 1, ADDERROR("High String Voltage", 2001));
IF(GETBIT(a1,1) = 1, ADDERROR("DC Arc Fault", 2002));
IF(GETBIT(a1,2) = 1, ADDERROR("String Reversed", 2011));
IF(GETBIT(a1,3) = 1, ADDWARNING("PV String Backfeed ", 2012));
IF(GETBIT(a1,4) = 1, ADDWARNING("Abnormal String", 2013));
IF(GETBIT(a1,5) = 1, ADDERROR("AFCI Self-test Fault", 2021));
IF(GETBIT(a1,6)= 1, ADDERROR("Short circuit between phase to PE ", 2021));
IF(GETBIT(a1,7) = 1, ADDERROR("Power Grid Failure ", 2032));
IF(GETBIT(a1,8) = 1, ADDERROR("Grid Undervoltage ", 2033));
IF(GETBIT(a1,9) = 1, ADDERROR("Grid Overvoltage", 2034));
IF(GETBIT(a1,10) = 1, ADDERROR("Unbalanced Grid Voltage", 2035));
IF(GETBIT(a1,11) = 1, ADDERROR("Grid Overfrequency", 2036));
IF(GETBIT(a1,12) = 1, ADDERROR("Grid Underfrequency", 2037));
IF(GETBIT(a1,13) = 1, ADDERROR("Grid Frequency Instability", 2038));
IF(GETBIT(a1,14) = 1, ADDERROR("Output Overcurrent ", 2039));
IF(GETBIT(a1,15) = 1, ADDERROR("Large DC of Output current ", 2040));
IF(GETBIT(a2,0) = 1, ADDERROR("Abnormal Leakage Current ", 2051));
IF(GETBIT(a2,1) = 1, ADDERROR("Abnormal Ground.", 2061));
IF(GETBIT(a2,2) = 1, ADDERROR("Low Insulation Res. ", 2062));
IF(GETBIT(a2,3) = 1, ADDERROR("High Temperature", 2063));
IF(GETBIT(a2,4) = 1, ADDERROR("Abnormal Equipment", 2064));
IF(GETBIT(a2,5) = 1, ADDERROR("Upgrade Failed", 2065));
IF(GETBIT(a2,6) = 1, ADDWARNING("License Expired", 2066));
IF(GETBIT(a2,7) = 1, ADDERROR("Abnormal Monitor Unit", 61440));
IF(GETBIT(a2,8) = 1, ADDERROR("Power collector fault ", 2067));
IF(GETBIT(a2,9) = 1, ADDERROR("Abnormal energy storage device", 2068));
IF(GETBIT(a2,10) = 1, ADDERROR("Active islanding", 2070));
IF(GETBIT(a2,11) = 1, ADDERROR("Passive islanding", 2071));
IF(GETBIT(a2,12) = 1, ADDERROR("Transient AC overvoltage", 2072));
IF(GETBIT(a2,15) = 1, ADDERROR("Abnormal PV module configuration", 2080));

Service Attributes

Model Name

MODBUSR(H, 30000, String, 15)

MODBUSR(H, 30015, String, 10)

MODBUSR(H, 30025, String, 10)

Model ID

MODBUSR(H, 30070, Uint16)

Number of Strings

MODBUSR(H, 30071, Uint16)

MPPT Number

MODBUSR(H, 30072, Uint16)

Time Zone

IF(MODBUSR(H, 43006, Int16) = 0, "UTC±00:00");
var time := MODBUSR(H, 43006, Int16)/0.6;
var zone := IF(MOD(time,100) = 0, time/100 + ":00", ROUND(time/100) + ":" + MOD(time,100));
RETURN (IF(time > 0, "UTC+" + zone, "UTC-" + zone ));

Inverter Efficiency

 MODBUSR(H, 32086, Uint16)/100 + "%"

Cabinet Temperature

MODBUSR(H, 32087, Int16) / 10 + " ℃ "

Insulation Resistance

MODBUSR(H, 32088, Uint16)/1000 + "MΩ "

DSP data collection

IF(GETBIT(MODBUSR(H, 32002, Uint16),0) = 1, "Yes", "No")

Service Actions

Time Zone

Parameters: Time Zone

MODBUSWNE(H, 43006, Int16, timz*60)

Active Power Electricity Meter

Electricity meter with active power (kW), reactive power, power factor, and power control actions for derating and compensation

Service Attributes

Active Power Peak of This Day

Reactive Power

Rated Power

Reactive Power Compensation (PF)

Reactive Power Compensation (Q/S)

Active Power Derating Percent (0.1%)

Active Power Derating (Fixed Value W)

Maximum Active Power

Maximum Apparent Power

Maximum Reactive Power (Fed to Grid)

Maximum Reactive Power (Absorbed from Grid)

Service Actions

Reactive Power Compensation (PF)	Set power factor from -1.0 to 1.0 for reactive power compensation
Reactive Power Compensation (Q/S)	Set reactive power ratio from -1.0 to 1.0
Active Power Derating Percent (%)	Limit inverter output power as percentage 0-100%

Active Power

Read demand

MODBUSR(H, 32080, Int32,2)/1000;

Service Attributes

Active Power peak of this day

MODBUSR(H, 32078, Int32, 2) + " kW"

Reactive Power

MODBUSR(H, 32082, Int32, 2)/1000 + " kVar"

Rated Power

MODBUSR(H, 30073, Uint32, 2)/1000 + " kW"

Reactive Power Compensation (PF)

MODBUSR(H, 40122, Int16)/1000

Reactive Power Compensation (Q/S)

MODBUSR(H, 40123, Int16)/1000

Active Power Derating percent (0.1%)

MODBUSR(H, 40122, Int16)/10 + "%"

Active Power Derating (fixed value W)

MODBUSR(H, 40126, Uint32, 2) + " W"

Maximum Active Power

MODBUSR(H, 30075, Uint32, 2)/1000 + " kW"

Maximum Apparent Power

MODBUSR(H, 30077, Uint32, 2)/1000 + " kVA"

Maximum reactive power (fed to grid)

MODBUSR(H, 30079, Uint32, 2)/1000 + " kVar"

Maximum reactive power (absorbed from grid)

MODBUSR(H, 30081, Uint32, 2)/1000 + " kVar"

Service Actions

Reactive Power Compensation (PF)

Parameters: Reactive power compensation

MODBUSWNE(H, 40122, Int16, pf*1000);

Reactive Power Compensation (Q/S)

Parameters: Reactive power compensation (-1, 1] (-1–1 rpc)

MODBUSW(H, 40123, Int16, rpc*1000);

Active Power Derating Percent(%)

Parameters: Active Power Derating Percent(%) (0–100 apdp)

MODBUSW(H, 40125, Uint16, apdp*10)

Battery Dimmer Read-only

Battery state of charge (SOC) as percentage — shows available energy in LUNA2000 storage

Service Attributes

Status

Battery running status — Offline, Standby, Running, Fault, or Sleep Mode

Grid Power Meter Electricity Meter Read-only

Active grid power (kW) and exported energy (kWh) from Smart Power Sensor — positive is export, negative is import

Service Attributes

Status	Power meter status — Normal or Offline
Type	Power meter type — 3-phase or 1-phase

Grid Power Meter

Read total consumption

MODBUSR(H, 37119, Int32) / 100

Read demand

MODBUSR(H, 37113, Int32) / 1000

Service Attributes

Status

IF(MODBUSR(H, 37100, Uint16) = 1, "Normal", "Offline");

Type

IF(MODBUSR(H, 37125, Uint16) = 1, "3 phase", "1 phase");

Daily Energy Variable Read-only

Energy generated today in kWh — resets at midnight

Total Energy Variable Read-only

Cumulative total energy generated since commissioning

DC Input Power Electricity Meter Read-only

Total DC power from all PV strings combined (kW) with grid-side measurements — phase voltages, currents, line-to-line voltages, and frequency

Service Attributes

A Voltage

B Voltage

C Voltage

A Current

B Current

C Current

AB Voltage

BC Voltage

CA Voltage

Frequency

DC Input Power

Read demand

MODBUSR(H, 32064, Int32, 2)/1000

Service Attributes

A Voltage

MODBUSR(H, 32069, Int16)/10 + " V"

B Voltage

MODBUSR(H, 32070, Int16)/10 + " V"

C Voltage

MODBUSR(H, 32071, Int16)/10 + " V"

A Current

MODBUSR(H, 32072, Int32, 2)/1000 + " A"

B Current

MODBUSR(H, 32074, Int32, 2)/1000 + " A"

C Current

MODBUSR(H, 32076, Int32, 2)/1000 + " A"

AB Voltage

MODBUSR(H, 32066, Int16)/10 + " V"

BC Voltage

MODBUSR(H, 32067, Int16)/10 + " V"

CA Voltage

MODBUSR(H, 32068, Int16)/10 + " V"

Frequency

MODBUSR(H, 32085, Uint16)/100 + " Hz"

Inverter Status Multi-value Switch Read-only

Inverter operating state — Idle, Starting, On-Grid, Shutdown, Grid Dispatch, IV Scanning, Spot-Check, Inspecting, DC Input Detection

Values / States: Initializing · Idle · Starting · On-Grid · Shutdown · Grid Dispatch · IV scanning · Spot-Check · Inspecting · DC input detection

Inverter Status

Read switch state

var reg := MODBUSR(H, 32089, Uint16);
IF(reg = 0, 0,
IF(reg < 4 OR reg = 40960,1,
IF(reg = 256, 2, 
IF(reg < 515, 3, 
IF(reg < 775, 4,
IF(reg = 1025 OR reg = 1026, 5, 
IF(reg = 1280 OR reg = 1281, 7,
IF(reg = 1536, 8, 
IF(reg = 2048, 6,
IF(reg = 2304, 9
))))))))))

Service Attributes

Full State

var state := MODBUSR(H, 32089, Uint16);
SWITCH(state, 0, "Idle: Initializing",
 1,"Idle: Detecting ISO", 
 2,"Idle: Detecting irradiation", 
 3, "Idle: Grid Detecting", 
 256, "Starting", 
 512, "On-Grid", 
 513, "On-Grid: Power Limit", 
 514, "On-Grid: self-derating", 
 768, "Shutdown: Fault", 
 769, "Shutdown: Command", 
 770, "Shutdown: OVGR", 
 771,"Shutdown: Communication disconnected", 
 772, "Shutdown: Power Limit", 
 773, "Shutdown: Start manually", 
 774, "Shutdown: DC Switch OFF",
 1025, "Grid dispatch:cos(Phi)-P curve",
 1026, "Grid dispatch:Q-U curve",
40960, "Idle: No irradiation",
1280, "Spot-check",
1281, "Spot-checking",
1536, "Inspecting",
1792, "SFCI self-check",
2048, "IV scanning",
2304, "DC input detection",
"Unknown"
 );

Grid Connection

var reg := MODBUSR(H, 32000,Uint16);
IF(GETBIT(reg,0) = 1, "Standby",
IF(GETBIT(reg,2) = 1 , "Normal Grid Connection",
IF(GETBIT(reg,3) = 1, "Grid connection with derating due to power rationing",
IF(GETBIT(reg,4) = 1, "Grid connection with derating due to inverter internal causes", "Not Connected"
)
)
)
)

Teleindication

var reg := MODBUSR(H, 32000,Uint16);
IF(GETBIT(reg,0) = 1, "Standby",
IF(GETBIT(reg,5) = 1 , "Normal Stop",
IF(GETBIT(reg,6) = 1, "Stop due to faults",
IF(GETBIT(reg,7) = 1, "Stop due to power rationing",
IF(GETBIT(reg,8) = 1, "Shutdown",
IF(GETBIT(reg,9) = 1, "Spot check",
IF(GETBIT(reg,1) = 1, "Grid Connected",
"Unknown State")
)
)
)
)
)
)

Locking Status

IF(GETBIT(MODBUSR(H, 32002, Uint16),0) = 1, "Unlocked", "Locked");

PV Connection Status

IF(GETBIT(MODBUSR(H, 32002, Uint16),0) = 1, "Connected", "Disconnected");

Startup time

var reg := MODBUSR(H, 32091, Uint32, 2);
var min := FLOOR(MOD(reg, 3600)/60);
var ho := FLOOR(MOD(reg,86400)/3600);
var minutes := IF(min<10, "0" + min, min);
var hours := IF(ho<10, "0" + ho, ho);
hours + ":" + minutes;

Shutdown time

var reg := MODBUSR(H, 32093, Uint32, 2);
var min := FLOOR(MOD(reg, 3600)/60);
var ho := FLOOR(MOD(reg,86400)/3600);
var minutes := IF(min<10, "0" + min, min);
var hours := IF(ho<10, "0" + ho, ho);
hours + ":" + FLOOR(minutes);

PV1 Current Variable Read-only

Service Attributes

PV1 Voltage

PV2 Current Variable Read-only

Service Attributes

PV2 Voltage

Connection: Modbus RTU • 9600 baud• 8N1 • Slave ID: $[SlaveId]

Possible improvements (12)

H:30035 Firmware Version — STR, 15 regs, read-only — useful for diagnostics
H:32010 Alarm 3 — Bitfield16, additional alarm bits not decoded in template readscript
H:32090 Fault Code — U16, specific fault code when device is in fault state
H:32095 Active Power (fast) — I32, kW, /1000, faster-updating active power reading
H:32108 Total DC Input Energy — U32, kWh, /100, cumulative DC energy input
H:32116 Monthly Energy — U32, kWh, /100, electricity generated this month
H:32118 Yearly Energy — U32, kWh, /100, electricity generated this year
H:37765 Battery Charge/Discharge Power — I32, W, positive=charging negative=discharging — would complement existing Battery SOC device
H:37121 Grid Exported Energy (unsigned) — U32, kWh, /100, unsigned variant of grid exported energy — complements the signed I32 already in template at H:37119
H:37123 Grid Accumulated Energy — U32, kWh, /100, total energy consumed from grid
H:40200 Power On — WO, E16, remote inverter power-on command
H:40201 Shutdown — WO, E16, remote inverter shutdown command

Download Template

Sources

Solar Inverter Modbus Interface Definitions (V3.0)
community.symcon.de 2026-03-28
PDF
SUN2000-(5KTL, 6KTL)-M0 User Manual
solar.huawei.com 2026-03-28
PDF
huawei-solar-lib — Python Modbus Library
github.com 2026-03-28