ABB FSCA-01 Modbus adapter (ACS580/880)
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 |
|---|
| control_word | 0 | U16 | 1 | |
| reference_1 | 1 | I16 | 1 | |
| reference_2 | 2 | I16 | 1 | |
| status_word | 3 | U16 | 1 | |
| actual_value_1 | 4 | I16 | 1 | |
| actual_value_2 | 5 | I16 | 1 | |
| status_word_enhanced | 50 | U16 | 1 | |
| actual_value_1_enhanced | 51 | I16 | 1 | |
| actual_value_2_enhanced | 52 | I16 | 1 | |
| reset_internal_error_registers | 89 | U16 | 1 | |
| failed_query_function_code | 90 | U16 | 1 | |
| internal_error_code | 91 | U16 | 1 | |
| failed_register | 92 | U16 | 1 | |
| last_written_register | 93 | U16 | 1 | |
| last_read_register | 94 | U16 | 1 | |
link settings as documented (unverified): RTU; default 9600 8N1; unit ID 1; FC 03,06,08,16,23,43
bench facts as documented (unverified)
| terminals | X1 |
| wiring notes | RS-485 Adapter Module |
| FC 43 device ID | supported |
| doc revision | 3AUA0000044530 REV A |
field reports — community-sourced, unverified (checked 2026-06-11)
- The FSCA-01 RS-485 adapter module Quick Guide (document 3AXD50000158546 Rev A) contains a critical pinout labeling error for connector X1. It incorrectly labels Pin 2 as 'DATA_A (Data positive)' and Pin 3 as 'DATA_B (Data negative)'. The correct pinout, as documented in the User's Manual (3AUA0000109533) and Hardware Manual (3AUA0000044521), is Pin 2 = DATA_B (Data positive) and Pin 3 = DATA_A (Data negative). Connecting them according to the Quick Guide will trigger a crosswise connection error (indicated by a flashing orange NETWORK LED). [source]
- confirmed: comms.baud_rates: [9600, 19200, 38400, 57600, 115200] — confirmed by parameter 4 (BAUD RATE) in the ABB FSCA-01 Modbus Protocol Manual (3AUA0000044530 REV A)
- confirmed: comms.default_baud: 9600 — confirmed by parameter 4 (BAUD RATE) default setting (0 = 9.6 kbit/s) in the ABB FSCA-01 Modbus Protocol Manual (3AUA0000044530 REV A)
- confirmed: comms.default_unit_id: 1 — confirmed by parameter 3 (STATION ID) default setting (1) in the ABB FSCA-01 Modbus Protocol Manual (3AUA0000044530 REV A)
- confirmed: comms.framing: ["RTU"] — confirmed by the ABB FSCA-01 Modbus Protocol Manual (3AUA0000044530 REV A) stating support for Modbus/RTU
- confirmed: comms.function_codes: [3, 6, 8, 16, 23, 43] — confirmed by the "Function codes" section in the ABB FSCA-01 Modbus Protocol Manual (3AUA0000044530 REV A) (03h, 06h, 08h, 10h, 17h, 2Bh/0Eh)
- confirmed: comms.parity: "N" — confirmed by parameter 5 (PARITY) default setting (0 = 8 NONE 1) in the ABB FSCA-01 Modbus Protocol Manual (3AUA0000044530 REV A)
- confirmed: comms.stop_bits: 1 — confirmed by parameter 5 (PARITY) default setting (0 = 8 NONE 1) in the ABB FSCA-01 Modbus Protocol Manual (3AUA0000044530 REV A)
- confirmed: facts.doc_revision: "3AUA0000044530 REV A" — confirmed by the title page of the ABB FSCA-01 Modbus Protocol Manual
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.