Register 11000 returns a value but the sign seems inverted. What is happening?

The wattsonic reports grid power with a sign convention where positive means import and negative means export. Some integration tools apply an automatic scale of -1 to invert this. Check your portal channel configuration and remove any scale inversion if you want raw sign convention as stored in the register.

Phase current registers read values that seem ten times too high. Why?

Registers 11010, 11012, and 11014 store current as uint16 with an implicit scale factor of 0.1, giving the result in amperes. If your integration reads the raw integer without applying this factor, the displayed value will be ten times larger than the actual current. Apply a scale of 0.1 to each current register.

The gateway connects to the inverter but all registers return zero or an error. What should I check?

Confirm the Modbus unit ID is set to 255 for TCP access via the LAN dongle. A wrong unit ID causes the inverter to ignore requests silently or return an exception. Also verify that no firewall rule on the router blocks port 502 between the ModbusCloud Gateway and the inverter IP.

Readings drop out intermittently every few minutes. Is this a known issue?

The wattsonic LAN dongle (espressif-based) is known to produce occasional TCP timeouts under continuous polling. Increasing the poll interval to 10 seconds or more and setting a TCP timeout of at least 10 seconds in the gateway configuration reduces dropout frequency significantly.

Free Modbus template: Solinteng wattsonic (grid)

The Solinteng wattsonic is a hybrid solar inverter sold under several OEM brand names, used in residential and small commercial PV-plus-storage installations. This Modbus TCP template targets the grid metering function of the wattsonic, reading total grid power at address 11000 and per-phase active power across phases A, B, and C at addresses 10994 to 10998. Phase currents for all three phases are available at addresses 11010 to 11014. Together, these registers give your ModbusCloud portal a complete picture of the grid connection point, enabling real-time import and export monitoring without additional external meters.

Name	Address	Function	Type	Unit	Access
power Total grid power, positive for import, negative for export.	11000	FC03	int32	W	R
currents_a Grid current on phase A, scaled by 0.1 to amperes.	11010	FC03	uint16	A	R
currents_b Grid current on phase B, scaled by 0.1 to amperes.	11012	FC03	uint16	A	R
currents_c Grid current on phase C, scaled by 0.1 to amperes.	11014	FC03	uint16	A	R
powers_a Active grid power on phase A, positive import, negative export.	10994	FC03	int32	W	R
powers_b Active grid power on phase B, positive import, negative export.	10996	FC03	int32	W	R
powers_c Active grid power on phase C, positive import, negative export.	10998	FC03	int32	W	R

Solinteng wattsonic (grid)

Overview

Use cases

Installation

Things to watch for

Registers (7)

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