Modbus TCP is enabled but the gateway cannot connect. Why?

By default, the SmartLogger restricts Modbus TCP access to a whitelist of up to five IP addresses. Open Settings, Modbus-TCP on the SmartLogger WebUI, add the ModbusCloud Gateway's IP address to the permitted list, and save. Also confirm firmware is at least V300R023C10SPC551.

The power register reads zero even though solar is generating. What is wrong?

The unit ID in the portal must match the logical address of the grid meter in the SmartLogger device list, not the inverter address. Open the SmartLogger WebUI, locate the meter under the device list, and copy its logical address into the ModbusCloud template unit ID field.

Phase current values look ten times too large. Is the scaling wrong?

The Huawei Modbus interface transmits current values with a gain factor of 10, meaning the raw register value must be divided by 10 to obtain amperes. Verify that the ModbusCloud template applies the correct scaling before displaying or logging the value.

The energy register returns an exception error code 3 on some firmware. Why?

Exception code 3 (illegal data value) on the int64 energy register at address 32349 is a known issue on older SmartLogger firmware. Upgrade to at least V300R023C10SPC551. If the error persists, check that the grid meter is named correctly, starting with Meter, in the SmartLogger device list.

Free Modbus template: Huawei SmartLogger (grid)

The Huawei SmartLogger is a data concentrator and monitoring gateway for PV systems and energy storage installations. This ModbusCloud template connects over Modbus TCP to the SmartLogger's built-in power meter interface and reads grid-side measurements: active power at the point of common coupling, cumulative energy, and per-phase currents across all three phases. Together these registers give your portal a complete real-time picture of grid import and export, enabling accurate energy balancing and anomaly detection without additional hardware.

Name	Address	Function	Type	Unit	Access
power Grid active power at the point of common coupling, signed.	32278	FC03	int32	W	R
energy Cumulative active energy at the grid connection point.	32349	FC03	int64	Wh	R
currents_a Phase A current at the grid meter, signed integer.	32272	FC03	int32	A	R
currents_b Phase B current at the grid meter, signed integer.	32274	FC03	int32	A	R
currents_c Phase C current at the grid meter, signed integer.	32276	FC03	int32	A	R