Why does my PowerFlex 40 fail after power has been cycled.

The information gives possible reasons why a PowerFlex 40 may be failing after a power cycle.

Excessive Heat Exposure can damaged critical parts of the PowerFlex 40 Drive
  • PCB Material: The PCB material used in the PF40 product is rated for heat stress at 105 degrees C. Discoloration subject to occur starting above 110C

  • Nylon Stand offs: This material rated for heat stress at 85 degrees C. Discoloration is subject to occur above 90C.

  • Failure mode of capacitor is consistent with exposure to heat stress
    • Bulge at top creating crown effect
    • Separation from PCB material at the solder point