All three phase power registers return zero. What is wrong?

Confirm that the Meter1/CT1 meter or CT clamp is physically connected and that its connection state register (address 38801) reads 1 (Connected). If the meter is disabled in the inverter's Feature Parm menu, the phase power registers will report zero even though Modbus communication is active.

Values seem ten times too large. Is there a scaling issue?

The FoxESS Modbus protocol documents a gain of 10 for registers 38816, 38818, and 38820, meaning raw register values are in units of 0.1 W. The OpenEMS template stores the int32 value directly without applying this divisor, so verify your display layer is not double-scaling. Treat the raw value as watts if readings appear plausible.

The gateway connects but no data appears for any register.

The FoxESS H3-Pro and H3-Smart require RS485 access via the EMS 485A/B pins on the large COM connector, not the Meter485 port used by older H3 models. Also confirm the baud rate is set to 9600, 8 data bits, no parity, 1 stop bit, which is the FoxESS default RS485 configuration.

The energy register reading dropped suddenly. Is data reliable?

Register 39617 is a cumulative uint32 counter. A sudden drop usually indicates a uint32 rollover or an inverter restart that reset the internal counter. Cross-reference with daily totals stored in your ModbusCloud portal history to reconstruct true accumulated values and set a baseline after any reset event.

Free Modbus template: FoxESS H3-Pro/Smart Series Hybrid Inverter (grid)

The FoxESS H3-Pro/Smart Series is a three-phase hybrid inverter designed for residential and light-commercial solar-plus-storage installations. This Modbus RTU template reads the built-in Meter1/CT1 grid interface, exposing per-phase active power on phases R, S, and T (registers 38816, 38818, and 38820) and cumulative grid-import energy (register 39617). Together these four registers give you a complete real-time and historical picture of grid consumption, enabling energy balance reporting and import-cost tracking directly inside your ModbusCloud portal.

Name	Address	Function	Type	Unit	Access
power_a Grid meter phase R (L1) active power, watts, signed.	38816	FC03	int32	W	R
power_b Grid meter phase S (L2) active power, watts, signed.	38818	FC03	int32	W	R
power_c Grid meter phase T (L3) active power, watts, signed.	38820	FC03	int32	W	R
energy Cumulative total energy taken from the grid, kWh.	39617	FC03	uint32	kWh	R