F42

Phase UW Short

Allen-Bradley · PowerFlex 4 Adjustable Frequency AC Drive

What does F42 mean?

A short circuit condition has been detected between motor phases U and W, or in the wiring connecting drive output terminals U and W to the motor. This indicates an unintended low-resistance path between these phases.

Additional Steps

Steps 1–2 are listed in Priority Fix.

  1. 3

    Measure resistance between motor phases U and W; expect a low resistance reading (continuity across the motor winding).

  2. 4

    Inspect the wiring between drive output terminals U, W and motor phases U, W for any physical damage or direct short circuits.

Source: Allen-Bradley PowerFlex 4 Adjustable Frequency AC Drive
Open Manual (Page 15)