Investigation sequence
Confirm output-related timing
If the trip occurs only after run command, the output insulation path becomes more likely than line input or keypad electronics.
Inspect cable and motor environment
Look for water ingress, crushed cable, damaged glands, conductive dust, overheated terminals and motor junction-box contamination.
Review output accessories
Identify output reactor, sine filter, contactor or surge absorber conditions and whether anything inappropriate is connected to the drive output.
Separate sensing fault
If external insulation evidence is clean, current/ground-sensing electronics may need board-level review.
Stop conditions
- Motor insulation test fails
- Cable damage is visible
- Trip appears with no motor/cable connected under permitted test conditions
- Unknown output-filter configuration
Linked records
The fault boundary includes motor winding insulation, motor cable, output contactor, contaminated terminal box, output filter and current/ground-fault sensing electronics.
Separates motor insulation, cable leakage, terminal contamination, output filters and internal sensing when a drive trips only after output voltage is applied.
Connects PWM command, isolated driver supply, gate components, short-circuit protection and the output bridge to overcurrent and repeat-module-failure symptoms.