Onicon FT-3000 flow meter

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
full_scale_flow_rate	0	F32BE	1	display unit
flow_rate_percent_full_scale	2	F32BE	1	%
flow_rate	4	F32BE	1	display unit
flow_velocity	6	F32BE	1	ft/s or m/s
t_plus_total_forward_flow_totalizer	8	U32BE	1	display unit
t_plus_overflow_decimal_point	10	U16	1
p_plus_partial_forward_flow_totalizer	11	U32BE	1	display unit
p_plus_overflow_decimal_point	13	U16	1
t_minus_total_reverse_flow_totalizer	14	U32BE	1	display unit
t_minus_overflow_decimal_point	16	U16	1
p_minus_partial_reverse_flow_totalizer	17	U32BE	1	display unit
p_minus_overflow_decimal_point	19	U16	1
process_flags	20	U16	1
samples_for_average_flow	21	U16	1	samples
equivalent_resistance_e1_common	22	U16	1	kΩ
equivalent_resistance_e2_common	23	U16	1	kΩ
voltage_e1_common	24	I16	1	mV
voltage_e2_common	25	I16	1	mV
voltage_recharging_terminals	26	U16	1	mV
residual_battery_capacity	27	U16	1	%
cpu_temperature	28	I16	1	F or C
board_temperature_t1	29	I16	1	F or C
board_temperature_t2	30	I16	1	F or C
sensor_coil_temperature	31	I16	1	F or C
latest_sensor_test_result_code	32	U16	1
active_alarms_count	33	U16	1

link settings as documented (unverified): RTU; default 19200 8E1; unit ID 1; FC 04,05,08; Device address range is 001 - 255. Default parity is Even. Default baud rate is 19200. MODBUS Reply Delay default is 20 ms (range 0 - 99 ms). MODBUS Timeout Interval default is 2 (valid settings: 1, 2, 3, 5).

bench facts as documented (unverified)

terminals	26 - Shield, 27 - RS485 Common, 28 - A - RS485 (+), 29 - B - RS485 (-)
A/B polarity	RS485 network cable connections are polarity sensitive (+ to + and - to -)
termination	Field settable 120Ω resistor via switches 1 and 2
shield/ground	Shield wires must not be connected to the FT-3000 Series. Shield drain wire should be left unterminated at the end of the cable and connected to earth only at the network master controller.
wiring notes	Transceiver is 3-wire, half-duplex, 1/8 unit load. Max of 32 devices per segment.
broadcast	not supported
protocol notes	MODBUS Reply Delay is configurable from 0 to 99 ms.
doc revision	DOC-0001665 Rev.F

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

confirmed: Document revision DOC-0001665 Rev.F corresponds to the Onicon FT-3000 Series MODBUS Supplement — confirmed by vendor documentation [1.3.1]
confirmed: Baud rates [1200, 4800, 9600, 19200, 38400, 57600, 115200] with default 19200 — confirmed by MODBUS Supplement Section 1.6
confirmed: Default Unit ID is 1, framing is RTU, parity is Even, stop bits is 1 — confirmed by MODBUS Supplement Section 1.6 and 2.1
confirmed: Function codes supported are 4, 5, 8 — confirmed by MODBUS Supplement Section 2.1
confirmed: Physical terminals (26 - Shield, 27 - RS485 Common, 28 - A - RS485 (+), 29 - B - RS485 (-)) and 120Ω termination switches — confirmed by MODBUS Supplement Section 1.3
confirmed: Shield wires must not be connected to the FT-3000 Series and should be left unterminated at the end of the cable — confirmed by MODBUS Supplement Section 3.1
confirmed: Register map addresses (0-based) match the Base 1 addresses in the memory map (e.g., full_scale_flow_rate @ 0, flow_rate @ 4, process_flags @ 20, active_alarms_count @ 33) — confirmed by MODBUS Supplement Section 2.2

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.