A Pareto analysis of downtime causes (as identified by repair technicians) revealed something that is puzzling to the plant engineer. The following three causes, when added up, comprise about 90% of failures:
- Loose connections in control cabinet.
- Motor insulation failure.
- Wiring problems.
The third one is a broad category, so the plant engineer spoke with a few technicians who selected this cause on their repair report sheet. They said the main problem is damaged insulation. The plant engineer visually inspected the wiring and noticed much of it looks as if it has been roughly handled, and it’s not very neat. But is this related somehow to the other two problems? He asked you to troubleshoot and recommend a solution.
There is a way in which these causes are probably related: poor methodology. The apparent rough handling of the wiring is likely the cause of both the insulation damage and those loose connections. The need to repair the wiring and connections subsequent to repairs is a classic case of “never enough time to do it right; always enough time to do it over.”
These problems have become a game of whack-a-mole. To end the wiring and connection issues, schedule downtime for rewiring (all new wire) the control cabinet.
Motor insulation failures will recur when the cause is not identified. Check first for voltage imbalance, which is the most likely cause.
