All registers return zero or no data after connecting. What is wrong?

Confirm the inverter's LAN dongle has a valid IP and is reachable from the ModbusCloud Gateway by pinging it. The inverter exposes Modbus TCP on port 502 with unit ID 255. Any other unit ID will return no response. Also verify the dongle is fully booted, which can take up to two minutes after power-on.

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

The phase current registers (11010, 11012, 11014) return raw uint16 values that must be divided by 10 to obtain amperes. If your integration or dashboard displays the raw register value without applying a 0.1 scale factor, the readings will appear inflated by a factor of ten.

The total power register reads an unexpected large negative number at midday. Why?

Register 11000 is a signed int32. Some integrations apply an additional scale of -1 to align with a positive-import convention. Check whether your portal configuration or any upstream software is inverting the sign. The raw register value follows the inverter's own sign convention, which may differ from your expected display orientation.

The gateway connects but readings drop out intermittently. How do I fix this?

The Wattsonic LAN dongle's Modbus TCP implementation can produce timeouts under continuous high-frequency polling. Set the poll interval to at least 10 seconds and use a 10-second read timeout. Reducing concurrent connections to one also helps, as the dongle handles sustained polling better with lower request rates.

Free Modbus template: Wattsonic wattsonic (grid)

The Wattsonic hybrid inverter is a three-phase residential energy storage system combining PV conversion, battery management, and grid metering in one unit. This template reads grid-side data from the wattsonic over Modbus TCP: total grid exchange power, per-phase active power across phases A, B, and C, and per-phase grid currents for all three phases. Together these seven registers give installers a complete real-time picture of what the site is importing or exporting at any moment. Use it in the ModbusCloud portal to track load imbalance, verify grid connection quality, and feed site-level energy dashboards.

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

Wattsonic wattsonic (grid)

Overview

Use cases

Installation

Things to watch for

Registers (7)

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