VFD’s Flashcards
What can cause an overcurrent fault in a vfd?
A break malfunctioning (drawing in too much current against the load, with the load in this case being the pulling in of the magnet to release the brake).
A traverse motor malfunctioning (ie a loose wire or ground fault etc can draw in too much current).
Can check the overloads at portal house for example on sr stacker reclaimer 46 and see if any OL’s are lit up.
A malfunctioning encoder reading a low rpm, not proportional to actual current inputted.
What’s a possible solution to overcurrent faults in a vfd for long travel?
You can identify which brakes/motors are causing issues and bypass them, after turning off the breaker ofc.
If the breaker is not turned off, caged breaks can try closing upon forcing of a bit or of regular brake release sequence during operation. A malfunctioning motor can also then draw in current, causing an overcurrent condition and subsequent vfd fault.
Would a vfd encoder fault in, for example, the elevating car in 46 cause the traverse vfd to also fault?
No.
How does the brake draw overcurrent?
The brake doesn’t release, and so the motor draws in over current as it fights against the brake.
