Vega VEGAPULS C 21 radar level sensor

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 confirmed at the hardware-verified rung and at no rung below it.

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
status	100	U16	1
pv_unit	104	U16	1
sv_unit	108	U16	1
tv_unit	112	U16	1
qv_unit	116	U16	1
pv_be	2002	F32BE	1
sv_be	2004	F32BE	1
tv_be	2006	F32BE	1
qv_be	2008	F32BE	1
pv_le	2102	F32LE	1
sv_le	2104	F32LE	1
tv_le	2106	F32LE	1
qv_le	2108	F32LE	1
measured_distance	2303	F32BE	1	m
absolute_echo_amplitude	2305	F32BE	1	dB
signal_quality	2314	F32BE	1	dB
filling_height	2316	F32BE	1	m
current_diagnostic_code	2300	U32BE	1
device_status	2307	U16	1

link settings as documented (unverified): RTU/ASCII; default 9600 8N1; unit ID 246; FC 03,04,06,08,16,17,43; Levelmaster protocol is also supported.

bench facts as documented (unverified)

terminals	Brown: Voltage supply (+), Blue: Voltage supply (-), Black: Modbus D+, White: Modbus D-, Shielding
A/B polarity	Black is D+ (Plus), White is D- (Minus)
termination	Make sure that the bus is terminated with suitable terminating resistors.
connector	Fixed cable
isolation	Electronics potential free up to 500 V AC
shield/ground	We recommend to connect the cable screening to ground potential at one end on the supply side when using shielded cable.
max registers/read	127
inter-frame delay	50 ms
serial register	2308
FC 43 device ID	supported
power	8 ... 30 V DC, Power consumption without/with bus communication typ. at 12 DC: 150 mW/330 mW, 24 V DC: 240 mW/420 mW
environment	Ambient temperature -40 ... +80 °C, Process temperature -40 ... +80 °C, Process pressure -1 ... 3 bar, Protection rating IP66/IP68 (3 bar, 24 h)
accuracy	Non-repeatability <= 2 mm, Temperature drift - Digital output < 3 mm/10 K, max. 5 mm
certifications	Class 4M8 acc. to IEC 60721-3-4, Class 6M4 acc. to IEC 60721-3-6, IK07 acc. to IEC 62262, IEC 60332-1-2, UL 1581
doc revision	Editing status: 2024-11-13, Document ID: 58343

field reports — community-sourced, unverified (checked 2026-06-11)

Failures of Modbus communication occurred in firmware versions prior to SW0785 (corrected in January 2022 update). [source]
An error in the close range measurement in the 'Bulk solids' application was present in earlier firmware versions (corrected in SW0785). [source]
confirmed: comms.baud_rates: [1200, 2400, 4800, 9600, 19200, 38400, 57600] — confirmed by VEGAPULS C 21 Modbus manual (Register 201)
confirmed: comms.default_baud: 9600 — confirmed by VEGAPULS C 21 Modbus manual (Register 201 default)
confirmed: comms.default_unit_id: 246 — confirmed by VEGAPULS C 21 Modbus manual (Register 200 default)
confirmed: comms.framing: ['RTU', 'ASCII'] — confirmed by VEGAPULS C 21 Modbus manual (Section 14.2)
confirmed: comms.function_codes: [3, 4, 6, 8, 16, 17, 43] — confirmed by VEGAPULS C 21 Modbus manual (Section 14.8)
confirmed: physical.terminals: Brown: Voltage supply (+), Blue: Voltage supply (-), Black: Modbus D+, White: Modbus D-, Shielding — confirmed by VEGAPULS C 21 Modbus manual (Section 5.2)
confirmed: quirks.max_read_registers: 127 — confirmed by VEGAPULS C 21 Modbus manual (Section 14.8, FC3/FC4 description)
confirmed: register_map: status @ 100, pv_unit @ 104, pv_be @ 2002, pv_le @ 2102, measured_distance @ 2303, absolute_echo_amplitude @ 2305, signal_quality @ 2314, filling_height @ 2316, current_diagnostic_code @ 2300, device_status @ 2307 — confirmed by VEGAPULS C 21 Modbus manual (Section 14.5, 14.6, 14.7)

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.

If your device isn't here, upload its register map. Generation is free, and the connector keeps the rung it earns under testing.

To prove a connector against your own device, order hardware verification. If it doesn't verify, you don't pay.

Platform builders can license the verified library: machine-readable maps, the firmware matrix, API access.