Braking resistor phase failure

What does F06922 mean?

This fault indicates a detected phase failure in one of the braking resistors. Depending on the fault value (U, V, or W), a specific phase's feeder cable may be open or disconnected. This can impair the drive's ability to dissipate regenerative energy, potentially leading to overvoltage faults or control issues.

• Open circuit in the wiring connecting the braking resistor to the drive's braking chopper terminals (e.g., R+, R-).
• Failure of one or more individual resistor elements within the braking resistor bank (e.g., open circuit due to thermal stress).
• Loose connection at the braking resistor terminal block or at the drive's braking chopper output terminals.
• Incorrect parameterization of the braking resistor monitoring function (e.g., P3-10 set too sensitively or P3-11 incorrect).
• Faulty internal current or resistance sensing circuit for the braking resistor within the drive unit.

Click steps to track your progress.

1. 1

   De-energize the drive and measure the resistance of the braking resistor bank directly at the drive's R+ and R- terminals (e.g., using a multimeter).

2. 2

   Inspect all wiring connections between the drive's braking chopper output and the braking resistor for loose terminals, corrosion, or damage.

3. 3

   If a multi-element resistor bank is used, individually measure the resistance of each resistor element (if accessible) to identify an open circuit.

4. 4

   Verify drive parameters related to braking resistor monitoring, such as P3-10 (Braking resistor monitoring threshold) and P3-11 (Braking resistor value).

5. 5

   Perform a functional test of the braking resistor by commanding a deceleration cycle and monitoring braking current (if external measurement points exist).