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ABB ACS580 VFD

ABB ACS580 VFD code 4991: Safe motor temperature

The extension module indicates a high motor temperature or disconnected thermistor, stopping the drive.

Safety first. This code involves a gas, flame or electrical hazard. Do not keep resetting it. Leave burner, gas train and high voltage work to a qualified technician. WERCS answers 24/7 at (877) 489-3727.
Code
4991
Name
Safe motor temperature
Controller
ABB ACS580 VFD
Type
Over temperature
What it does
Fault: the equipment trips and stops
Risk
RED Specialist territory
Reset
Needs a manual reset
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
  • The 2 common causes listed for this code
  • The step by step check for this problem, one check at a time
  • 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 4991 mean?

The extension module indicates a high motor temperature or disconnected thermistor, stopping the drive.

Is ABB ACS580 VFD code 4991 dangerous?

It is graded red, specialist territory: it involves a burner, gas, flame or safety lockout, so leave the repair to a qualified technician.

How do I fix ABB ACS580 VFD code 4991?

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.

Other ABB ACS580 VFD codes

All 191 ABB ACS580 VFD codes · Every fault code