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Table 7-2. - Controller Troubleshooting Tips - Continued
| b. Interrupting excessively high current | Check for grounds, shorts, or excessive motor currents |
| c. Excessive jogging | Install larger device rated for jogging service |
| d. Weak tip pressure | Replace contacts and springs; check carrier for damage |
| e. Dirt on surfaces | Clean contacts; reduce exposure |
| f. Short circuits or ground fault | Remove fault; be sure fuse/breaker size is correct |
| g. Loose connection | Clean then tighten |
| h. Sustained overload | Check for excessive motor current or install larger controller |
| Corrosion | Excess moisture; salt air; acid fumes |
| Excess wear or friction | Abrasive dust; high inertia load; excess temperature |
| Failure to break arc | Too much current; too much voltage (dc); misapplication; too much inductance |
| Failure to hold load | Worn parts; out of adjustment; misapplication; failure to use recommended substitute parts |
| Failure to make contact | Mechanical damage; dirt; corrosive; wear allowance gone |
| Failure to open or close | Low voltage; coil open; mechanical binding; mechanical overload; no voltage; wrong coil: shorted turns; excessive magnet gap: mechanical binding; gummy substance on magnet faces: air gap in magnet destroyed; contact tip welded; voltage not removed; corrosion; scale; dirt; operating above rated pressure; damaged motor |
| Failure to operate properly | Coils connected wrong; wrong coil; mechanical binding |
| Failure to release | Improper adjustment; coil not energized; mechanical binding: low voltage or current; coil open; shorted turns |
| Failure to reset overload relay | Mechanical binding; worn parts; dirt; broken mechanism; corrosion; worn parts; resetting to soon |
| Failure to set overload relay | Improper adjustment; mechanical binding; coil not de- energized; worn parts |
| Failure to time out (on motor operated relays) | Mechanical binding; worn parts; motor damaged; no voltage to motor; dirt |
| Failure to trip (during overload conditions) | Heater incorrectly sized; mechanical binding; relay previously damaged by short circuit current; dirt; corrosion; motor and relay in different ambient temperatures |
| Fast trip (on overload relays) | High temperature; wrong heaters |
| Flashover | Jogging; short circuits; handling too large motor; moisture; acid fumes; gases; dirt |
| Heating | Overcurrent; loose connection; spring clips loose or annealed; oxidation: corrosion |