Mastervolt MasterBus-Modbus interface

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
idal_idb_hi	0	U16	1
idb_lo	1	U16	1
tab_nr	2	U16	1
index	3	U16	1
value	4	F32LE	1

link settings as documented (unverified): RTU; default 19200 8E?; unit ID 1; FC 23; Uses Modbus function 23 (0x17) Read/Write Multiple Registers Protocol to bridge to MasterBus.

bench facts as documented (unverified)

terminals	Screw terminal
A/B polarity	B line, A line, Ground
termination	MasterBus Terminating device included
connector	Screw terminal
wiring notes	Din rail mounting: Yes, Din rail 30 mm [1.2 inch]
max registers/read	6
response timeout	3000 ms
protocol notes	Only supports Modbus function code 23 (0x17). Read Starting Address must be 0, Quantity to Read must be 6, Quantity to Write must be 6.
power	350 mW
environment	Protection degree: IP 21
certifications	CE, 2004/108/EC (EMC directive), 2011/65/EU (RoHS directive)
doc revision	v 1.4 September 2014

generated by gemini:gemini-3.5-flash · harvested from http://www.marinewarehouse.net/images/mastervolt/Web/ManualModbus140918EN.pdf (Mastervolt); 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.