Reads SMA Sunny Boy inverter values via Modbus TCP.
Overview
This template reads AC and DC electrical parameters, energy yield, and temperature data from SMA Sunny Boy inverters via Modbus TCP. All registers are read-only, covering grid voltage, frequency, power, daily yield, total yield, DC voltage, current, and power.
Key readings
Grid Voltage L1
Grid Frequency
AC Power
Daily Yield
Total Yield
DC Voltage, Current, Power
Use cases
Monitor real-time AC power output and grid voltage on a live cloud dashboard for residential PV customers.
Track daily and total energy yield remotely to verify system performance against design estimates.
Create an alert when AC power drops to zero during daylight hours to detect potential inverter faults.
Generate monthly yield reports for multiple SMA Sunny Boy installations from a single platform.
Compare DC voltage and current readings across string inverters to identify panel degradation or shading issues.
Installation
1Connect the ModbusCloud gateway (MCG or MLP series) to the same local network as the SMA Sunny Boy inverter via Ethernet.
2Enable Modbus TCP on the SMA Sunny Boy through the inverter's web interface or SMA Sunny Portal, and note the configured IP address and Modbus unit ID.
3Log in to the ModbusCloud platform, add a new device, and import the SMA Sunny Boy template from the template library.
4Enter the inverter's IP address and Modbus unit ID in the device configuration on ModbusCloud.
5Verify the connection by checking that Grid Voltage L1 and AC Power values appear on the live data view.
6Optionally confirm the connected model by reading the Inverter Type register at address 30053.
Things to watch for
01
Modbus TCP connection fails. What should I check?
Make sure Modbus TCP is explicitly enabled on the SMA Sunny Boy. This setting is often disabled by default. You can enable it via the inverter's web interface. Also verify that the gateway and inverter are on the same subnet and that no firewall is blocking TCP port 502.
02
All register values show as 0 or NaN. Why?
The SMA Sunny Boy uses uint32 and int32 registers, which each span two Modbus words. Confirm that your gateway is configured to read 32-bit registers with the correct byte order (Big Endian, also called AB CD word order). An incorrect word swap will produce invalid values.
03
Which Total Yield register should I use?
The template includes two total yield registers. Address 30529 returns the value in Wh for higher precision, while address 30531 returns it in kWh. Choose the one that best matches your reporting or dashboard requirements.
04
Does this template work with SMA Sunny Boy models that have Wi-Fi only?
Modbus TCP requires an Ethernet connection. If your Sunny Boy model only has Wi-Fi, you will need to confirm it supports Modbus TCP over its wireless interface or use an Ethernet adapter if available. Most current Sunny Boy models include an Ethernet port.
Registers (12)
12 read / 0 write
Name
Address
Function
Type
Unit
Access
Inverter Type
30053
FC03
uint32
R
GridVoltageL1
30783
FC03
uint32
V
R
GridFrequentie
30803
FC03
uint32
Hz
R
Power
30775
FC03
int32
W
R
DailyYield
30537
FC03
uint32
kWh
R
TotalYield
30531
FC03
int32
kWh
R
TotalYield Wh
30529
FC03
uint32
Wh
R
DC Current
30769
FC03
int32
A
R
DC Voltage
30771
FC03
int32
V
R
DC Power
30773
FC03
int32
W
R
Heat sink temperature
34109
FC03
int32
°C
R
Internal temperature
34113
FC03
int32
°C
R
Working with Modbus in your projects?
ModbusCloud is the hardware-plus-software platform that installers use to monitor, visualise and control Modbus devices from one portal. This template is one of hundreds you can use right away.
