I've repaired a few of these Kone V3F16L drives. Usually the problem is a blown IGBT module, type BSM50GP120. When this fails it generally takes with it a bunch of diodes and resistors plus the occasional opto-coupler and capacitor. The high voltage inside the IGBT module shorts to one or more of the the insulated gates. The last repair lasted about 6 weeks. Has anyone got any idea why these drives fail like this? Could it be something to do with the pair of contactors carrying the motor feeds, an unbalanced 3 phase supply or just an under-rated drive for the particular lift? The one in question is in a theatre and could get very hot with a lot of continuous use...
