WEG CFW300 drive

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
motor_speed	2	U16	1	Hz
motor_current	3	U16	0.1	A
acceleration_time	100	U16	0.1	s
deceleration_time	101	U16	0.1	s
serial_watchdog	314	U16	0.1	s
serial_interface_status	316	U16	1
status_word	680	U16	1
motor_speed_13_bits	681	I16	1
serial_control_word	682	U16	1
serial_speed_reference	683	I16	1

link settings as documented (unverified): RTU; default 19200 8E1; unit ID 1; FC 03,04,06,16,43; The mini USB connector is not USB compatible and is only used for the remote keypad.

bench facts as documented (unverified)

terminals	25: RS485-A(-), 26: RS485-B(+), 27: GND, 28: Shield(PE), 29: N.C.
A/B polarity	A is (-), B is (+)
termination	S1.1 = ON and S1.2 = ON to enable termination resistor
connector	Control terminal and mini USB
isolation	Electrically isolated
shield/ground	Terminal 28 Shield (PE) must be grounded
wiring notes	Maximum bus length of 1000 meters.
response timeout	10 ms
broadcast	supported
protocol notes	The telegrams for request, as well as for response, cannot exceed 64 bytes. Transmitted values are always integer.
identification notes	Supports Read Device Identification (FC43) with Object 00h (VendorName), Object 01h (ProductCode), and Object 02h (MajorMinorRevision).
FC 43 device ID	supported
doc revision	10003806158 / 02

⚠ disputed: Baud rates [1200, 2400, 4800, 9600, 19200, 38400, 57600] — disputed by WEG CFW300 Modbus RTU User Manual (P310 only supports 9600, 19200, 38400, 57600, and 76800 bits/s; 1200, 2400, and 4800 are not supported)

⚠ disputed: Physical connector is 'Control terminal and mini USB' on the drive — disputed by WEG CFW300 Modbus RTU User Manual and product documentation (the CFW300 drive does not have built-in RS485 or USB; these interfaces are only available via optional plug-in modules such as CFW300-CRS485)

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

A user reported that they could write the speed reference to P683 and read it back from P001, but the motor output speed (P002) did not change and remained at 60Hz, even though P221 and P222 were set to 9 (Serial). The issue was resolved by performing a factory reset of the drive and re-entering the parameters. [source]
confirmed: Default baud rate is 19200 — confirmed by WEG CFW300 Modbus RTU User Manual (P310 default is 1, which corresponds to 19200 bits/s) [4.1.1]
confirmed: Default unit ID is 1 — confirmed by WEG CFW300 Modbus RTU User Manual (P308 default is 1)
confirmed: Framing is RTU — confirmed by WEG CFW300 Modbus RTU User Manual
confirmed: Function codes 3, 4, 6, 16, 43 are supported — confirmed by WEG CFW300 Modbus RTU User Manual (Section 5.1)
confirmed: The mini USB connector on the RS485 module is not USB compatible and is only used for the remote keypad — confirmed by WEG CFW300 Modbus RTU User Manual (Section 2.1)
confirmed: Supports Read Device Identification (FC43) with Objects 00h, 01h, and 02h — confirmed by WEG CFW300 Modbus RTU User Manual (Section 5.2)
confirmed: Maximum bus length of 1000 meters — confirmed by WEG CFW300 Modbus RTU User Manual (Section 2.1.2)
confirmed: RS485 terminals are 25: RS485-A(-), 26: RS485-B(+), 27: GND, 28: Shield(PE), 29: N.C. — confirmed by WEG CFW300 Modbus RTU User Manual (Table 2.1)

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.