Bronkhorst EL-FLOW/IN-FLOW digital instruments (Modbus slave)

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
measure	32	U16	1	%
setpoint	33	U16	1	%
analog_input	35	U16	1
control_mode	36	U16	1
temperature_u16	1063	U16	1
counter_value_u16	3329	U16	1
capacity	33128	F32BE	1
fmeasure	41216	F32BE	1
fsetpoint	41240	F32BE	1
temperature	41272	F32BE	1
counter_value	59400	F32BE	1
counter_limit	59416	F32BE	1
valve_output	61960	U32BE	1
density_actual	62584	F32BE	1

link settings as documented (unverified): RTU/ASCII/TCP; default 19200 8E1; unit ID 1; FC 03,06,16,08,17; Modbus RTU and ASCII default to 19200 baud, address 1. Parity is even by default (configurable on MBC3/EL-FLOW Base). Modbus TCP server port is 502, supporting up to 4 clients.

⚠ Not following the guidelines could result in personal injury and/or damage to the equipment. — Starkest reads only; we never write a control register.

bench facts as documented (unverified)

terminals	RJ45, M12, DB9
A/B polarity	D0 Modbus (A/A'), D1 Modbus (B/B')
termination	No integrated termination. External 120 Ohm resistors recommended.
connector	RJ45 modular jack, M12 circular connector, DB9 female connector
shield/ground	Shielded cables required
wiring notes	Pin layout on RJ45 is vendor-specific and differs from Modbus standard.
max registers/read	125
response timeout	100 ms
broadcast	supported
protocol notes	Maximum message size for Read Holding Registers is 100 bytes at 9600 baud, 200 bytes at 19200 baud, and 400 bytes at 38400 baud.
model register	61704
serial register	61720
firmware register	61736
identification notes	Report Slave ID (FC17) returns a string containing ident number, version, and serial number.
FC 43 device ID	not supported
power	15...24 Vdc
certifications	CE
doc revision	9.17.035AF

generated by gemini:gemini-3.5-flash · harvested from https://products.bronkhorst.com/media/vs1lwo3b/917035-manual-modbus-slave-interface.pdf (Bronkhorst); manual-faithful — the document's claims, panel risk: HIGH — independent re-derivation disagrees on specific fields; 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.