What causes a PID Feedback Error on an Altivar Process Drive?

A PID Feedback Error (PFMF) typically occurs when the control loop loses proper feedback, often due to sudden or large process changes.

Common cause:

• A rapid change in the process, such as a valve opening quickly
• This causes the drive to:
  • Accelerate to maximum speed to meet the demand
  • Lose stable feedback control because the process variable is no longer properly regulated
• As a result, the PID loop is effectively open (no valid feedback response), triggering a PID Feedback Error (PFMF)

How to resolve it:

If feedback monitoring is not required for your application:

1. Navigate to:
   [Pump Functions] → [Feedback Monitoring]
2. Set Feedback Monitoring to:
   NO

When to use this fix:

• When the process includes intentional rapid changes (e.g., valve operation)
• When temporary or unstable feedback signals are expected
• When the feedback monitoring protection is causing unnecessary trips

Important note:

Disabling feedback monitoring removes protection against loss of PID feedback. Only do this if it is safe and appropriate for your process.

If this article does not answer your question, check out our FAQ database that has answers to more commonly asked questions:

Frequently Asked Questions - Schneider Electric (se.com)

If this FAQ did not solve your issue, you can call us at 1-888-778-2733 Option 2 and then 4 or e-mail us atdrive.products.support@se.comto create a case with our Technical Support Team.

If you are not located in North America, please contact your local Customer Care Center for assistance:

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