Fox ESS on-grid inverter

Register map(s) for this device, each at the trust rung it earned. Addresses are 0-based as on the wire; word order and scaling are only confirmed at the hardware-verified rung.

interop-verified

Read + decoded cleanly over a real network vs an independent third-party Modbus test server (transport and framing; reads are remapped into the server's register window, so the map's own addresses are NOT exercised). Does NOT prove word order/scaling against the actual device.

point	address (0-based)	type	scale
master_state	10500	U16	1
grid_yield_today	10503	U16	0.1
grid_yield_total	10504	U32BE	0.1
feed_in_power	10506	I16	1
output_power	10507	I16	1
load_power	10508	I16	1
bat_power	10509	I16	1
grid_volt_r	10700	U16	0.1
grid_current_r	10701	I16	0.1
grid_freq_r	10702	U16	0.01
grid_power_r	10703	I16	1
grid_volt_s	10704	U16	0.1
grid_current_s	10705	I16	0.1
grid_freq_s	10706	U16	0.01
grid_power_s	10707	I16	1
grid_volt_t	10708	U16	0.1
grid_current_t	10709	I16	0.1
grid_freq_t	10710	U16	0.01
grid_power_t	10711	I16	1
pv1_volt	10800	U16	0.1
pv1_current	10801	U16	0.1
pv1_power	10802	U16	1
pv2_volt	10803	U16	0.1
pv2_current	10804	U16	0.1
pv2_power	10805	U16	1
charger_temp	11200	I16	1
inv_temp	11201	I16	1
ambient_temp	11202	I16	1
bat1_volt	11500	U16	0.1
bat1_current	11501	I16	0.1
bat1_power	11502	I16	1

link settings as documented (unverified): RTU; default 9600 8N1; unit ID 1; FC 03,04,06,16,69

bench facts as documented (unverified)

terminals	RS485
max registers/read	125
model register	10020
serial register	10036
firmware register	10055
doc revision	V1.02

generated by gemini:gemini-3.5-flash · harvested from http://donno.ddnsgeek.com/history-unit/Hardware/FoxESS.Modbus.On.Grid.solar.inverter.Modbus.Protocol.pdf (Fox ESS); manual-faithful — the document's claims, panel risk: ELEVATED — panel is not confident; proved interop-verified on 2026-06-10 · recorded 2026-06-10

The trust ladder

Each rung states what it proved and what it did not. Gray until proven; green is earned by hardware only.

generated — A prompt produced it. Unproven — anyone can regenerate this.
structure-verified — Decode path is structurally sound (addresses, widths, finite values). Does NOT prove word order or scaling.
interop-verified — Read + decoded cleanly over a real network vs an independent third-party Modbus test server (transport and framing; reads are remapped into the server's register window, so the map's own addresses are NOT exercised). Does NOT prove word order/scaling against the actual device.
simulator-verified — Decoded correctly against a protocol emulator seeded with known-true values — catches word-order/scaling errors vs the emulator, not the physical device.
hardware-verified x1 — Matched a real device with operator-attested readings as ground truth — the only rung that confirms word order + scaling on the wire.

Have a device that isn't here? Upload its register map — generation is free, and the connector earns its rung by being proven, not claimed.

Need it proven on your own device? Hardware verification — if it doesn't verify, you don't pay.

Building a platform? License the verified library — machine-readable maps, firmware matrix, API access.