What causes a preload problem in ABB PQFS Industrial Electrical?
- JJennifer CookSep 4, 2025
If you're encountering a preload problem with your ABB Industrial Electrical system, it means the DC capacitors couldn't be preloaded at startup, possibly because the voltage increase on the DC capacitors during the preload phase isn't high enough. To troubleshoot: * Measure the three line voltages to ensure they are within acceptable limits. * Verify the fuses (PF1 and PF2) and the resistors (R1 and R2) of the preload circuit (A001). * Inspect the DC-bus for traces of damage that may have caused a short circuit on the DC side of the IGBT module or on the DC voltage measurement board.