ABB ACS580 VFD
ABB ACS580 VFD code A784: Motor disconnect
All three output phases are disconnected from the motor, which prevents the drive from running it.
- Code
- A784
- Name
- Motor disconnect
- Controller
- ABB ACS580 VFD
- Type
- General fault
- What it does
- Warning: the equipment keeps running and flags a problem
- Risk
- GREEN In your wheelhouse
- Reset
- Clears on its own when the condition goes away
- Source
- The manufacturer's manual (subscribers see which manual and page)
Updated November 4, 2026
How to fix it
Subscribers get:
- What to do next, in plain words
- What the manual says to do, and the page it is on
- Booking a live video call with Ben, a master booth technician ($250/hr, paid per call)
Questions about this code
What does ABB ACS580 VFD code A784 mean?
All three output phases are disconnected from the motor, which prevents the drive from running it.
Is ABB ACS580 VFD code A784 dangerous?
It is graded green: in a working tech's wheelhouse with standard tools and low risk.
How do I fix ABB ACS580 VFD code A784?
The manual's fix and the step by step check for this code are in WERCS Diagnose, plans from $49 a month. For help right now, WERCS answers 24/7 at (877) 489-3727.