Wattsonic - Schmachtl Sun Energy Box

Use cases

• Monitor PV string production and battery state of charge on a live cloud dashboard for each installation.
• Create an alert when battery SOC drops below a defined threshold to notify the end customer or installer.
• Track grid injection and purchasing energy over time to verify self-consumption optimization.
• Log inverter temperature sensor readings to detect cooling issues before they cause shutdowns.
• Review fault flag registers remotely to diagnose inverter errors without a site visit.
• Compare phase voltages and currents across L1 to L3 to identify grid imbalance conditions.

Installation

1. 1Connect the Modbus RTU wiring (A, B, GND) between the Wattsonic Sun Energy Box RS485 port and the ModbusCloud gateway (MCG or MLP series).
2. 2Set the Modbus slave address on the inverter to match the address configured in the ModbusCloud template, typically address 1.
3. 3Verify the serial communication parameters on the inverter (baud rate, parity, stop bits) and ensure the gateway uses identical settings.
4. 4Import the Schmachtl Sun Energy Box template from the ModbusCloud template library into your project.
5. 5Confirm that register data appears correctly on the ModbusCloud dashboard, paying attention to 32-bit register values and their scaling.
6. 6If upgrading from a template version prior to 1.0.2, verify that the Battery_Power scaling factor is correct after import.

Things to watch for

01

Which baud rate and parity settings does the Wattsonic Sun Energy Box use by default?

Consult the inverter manual for the factory default serial settings. Common defaults are 9600 baud, 8N1, but this can vary by firmware version. Always match the gateway settings exactly.

02

Why do some power or energy values show as zero or abnormally large numbers?

Several registers use int32 or uint32 data types that span two consecutive Modbus registers. Ensure the gateway is configured for 32-bit reads with the correct byte and word order. Incorrect order will produce nonsensical values.

03

I upgraded from a template version before 1.0.2 and battery power readings seem wrong. What should I check?

Version 1.0.2 adjusted the Battery_Power register scaling. After upgrading, open the register configuration and verify the scale factor matches the current template definition.

04

The template says Modbus RTU, but the protocol listed is Modbus TCP. Which one applies?

The Wattsonic inverter communicates via Modbus RTU over RS485. If your ModbusCloud gateway provides an RTU-to-TCP bridge, the cloud connection uses TCP while the physical link to the inverter remains RTU.

Registers (92)

92 read / 0 write

More Wattsonic templates

Wattsonic wattsonic (pv)

Wattsonic

Modbus TCP

1 registers

Wattsonic Wattsonic GEN3 (battery)

Wattsonic

Modbus TCP

3 registers

Wattsonic Wattsonic GEN3 (pv)

Wattsonic

Modbus TCP

1 registers

Wattsonic wattsonic (battery)

Wattsonic

Modbus TCP

3 registers

Wattsonic Wattsonic GEN3 (grid)

Wattsonic

Modbus TCP

7 registers

Wattsonic wattsonic (grid)

Wattsonic

Modbus TCP

7 registers

More RTU templates

connecdoor.controller

connecdoor

Modbus RTU

Controls and monitors smart door access points via RS485

0 registers53

Alnor HRU-P

Alnor Systemy Wentylacji Sp. z o. o.

Modbus RTU

Controls Alnor HRU-P heat recovery ventilation units via Modbus RTU.

49 registers7

Alnor HRU

Alnor Systemy Wentylacji Sp. z o. o.

Modbus RTU

Controls and monitors Alnor heat recovery ventilation units via Modbus RTU.

29 registers13

Heidelberg Wallbox Energy Control

AMPERFIED GmbH

Modbus RTU

Controls and monitors Heidelberg Wallbox Energy Control EV charger via Modbus RTU.

22 registers67

Belimo Air-Water Actuator Modbus RTU

Belimo

Modbus RTU

Controls communicative damper and valve actuators via Modbus RTU.

20 registers46

Siemens 7KT1665 (charge)

Siemens

Modbus RTU

5 registers