ABB ACS880 Warning AFE1 Emergency Stop (OFF2)

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Getting the AFE1 warning on your ABB ACS880 drive? Learn what the OFF2 Emergency Stop means, how to reset the physical safety circuit, and how to get your VFD running again.

ABB ACS880 Warning AFE1 Emergency Stop (OFF2)

 

If you are working with an ABB ACS880 industrial drive and the control panel suddenly displays Warning AFE1, your drive has entered a safety state. This is not a hardware failure; rather, it is the drive responding to a specific command to shut down immediately.

In this guide, we will break down what the AFE1 warning means, the difference between OFF2 and other stop modes, and the exact steps you need to take to restore operation.

What Exactly is AFE1 (OFF2)?

The AFE1 code indicates that the drive has received an Emergency Stop (OFF2) command. In the ABB ecosystem, "OFF2" stands for Coast-to-Stop.

When this signal is triggered, the drive immediately disconnects power from the motor windings. The motor is left to spin down freely based on its own inertia (coasting). This is typically used when a process is unsafe and the motor must be electrically isolated from the drive as fast as possible.

Common Causes of the AFE1 Warning

  • Physical E-Stop Button: A hardwired emergency stop button on the machine or control cabinet has been pressed.
  • PLC Logic: The master controller (PLC) has sent a digital command through the fieldbus (PROFINET, EtherNet/IP, etc.) to trigger a safety stop.
  • Safety Relay Trip: An upstream safety module (like a light curtain or gate switch) has opened the safety loop.
  • Parameter Misconfiguration: The drive is looking for a signal on a terminal that isn't currently wired.
Safety Note: An Emergency Stop happens for a reason. Never reset an E-stop until you have verified that the machine area is clear and it is safe for the equipment to move.

Step-by-Step Solution

1. Verify Site Safety

Walk the machine perimeter. Ensure no personnel are performing maintenance and there are no mechanical obstructions that caused the stop. If the E-stop was pressed because of a mechanical jam, clear the jam first.

2. Reset the Physical Hardware

Locate the physical Emergency Stop push button that was activated. Most E-stops are "latching," meaning they stay down once pressed.

  • Twist or pull the E-stop button back to its normal (ready) position.
  • If your system uses a safety relay, you may need to press a "Safety Reset" button on the cabinet door to re-energize the safety loop.

3. Clear the Drive Warning

Once the physical signal is restored (the drive sees 24V DC on its safety input or a '1' in the control word), the AFE1 warning may still linger on the screen.

  • Press the [Reset] button on the Assistant Control Panel.
  • The warning should disappear, and the drive status should change to "Ready."

4. Restart the Drive

For safety reasons, the ACS880 will not restart automatically after an AFE1 event. You must provide a fresh Start command (toggle your start switch or send a new start bit from the PLC) to get the motor spinning again.

Advanced Troubleshooting: Unintentional AFE1

If the AFE1 warning appears but no one pressed an E-stop, you need to check the Source of the command in the drive's parameters.

  • Check Parameter 21.05: Navigate to Menu > Parameters > Group 21 (Start/Stop Mode) and look at 21.05 Emergency stop source.
  • This parameter tells you where the drive is looking for the OFF2 signal (e.g., DI1, DI6, or a specific bit in the Fieldbus Control Word).
  • Check the wiring at that specific terminal. A loose wire or a blown 24V control fuse is a common culprit for "ghost" AFE1 warnings.

Summary Checklist

Action Check For
Mechanical Check Is it safe to run? Clear all hazards.
Button Reset Pull/Twist all E-stop buttons to the "High" position.
Wiring Check Ensure 24V DC is present at the input defined in Parameter 21.05.
PLC Check Verify the Fieldbus Control Word isn't holding the OFF2 bit low.

 

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