ABB Terra AC wallbox EV charger

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	unit
firmware_version	16388	U32BE	1
user_settable_max_current	16390	U32BE	0.001	A
error_code	16392	U32BE	1
socket_lock_state	16394	U32BE	1
charging_state	16396	U32BE	1
charging_current_limit	16398	U32BE	0.001	A
charging_current_l1	16400	U32BE	0.001	A
charging_current_l2	16402	U32BE	0.001	A
charging_current_l3	16404	U32BE	0.001	A
voltage_l1	16406	U32BE	0.1	V
voltage_l2	16408	U32BE	0.1	V
voltage_l3	16410	U32BE	0.1	V
active_power	16412	U32BE	1	W
energy_delivered	16414	U32BE	1	Wh
communication_timeout_read	16416	U16	1	second
set_charging_current_limit	16640	U32BE	0.001	A
lock_unlock_socket_cable	16643	U16	1
start_stop_charging_session	16645	U16	1
communication_timeout_write	16646	U16	1	second

link settings as documented (unverified): RTU/TCP; baud 4800/9600/19200/38400/57600/115200; FC 03,06,16; Recommended polling interval for readable data is 30s~90s.

⚠ In case of unhealthy, charger could get into error state and stop the charging session. — Starkest reads only; we never write a control register.

bench facts as documented (unverified)

connector	RS485 and TCP/IP
wiring notes	Many chargers could be daisy chained by wiring as a serial line.
protocol notes	Based on the polling operation (at least read a register) and configurable timeout period, charger could understand whether Modbus communication is healthy or not.
serial register	4000h
firmware register	4004h
certifications	IEC 61851-1
doc revision	1.7

generated by gemini:gemini-3.5-flash · harvested from https://library.e.abb.com/public/4124e0d39f614ba7b0a7a6f7a2ce1f99/ABB_Terra_AC_Charger_ModbusCommunication_v1.7.pdf (ABB); 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.