​Vibration-motor failures fall into seven classic categories

Use the checklist below for fast on-site troubleshooting and long-term prevention.

1.Failure to start

Root causes:missing phase/low voltage;open or shorted winding;seized bearing or foreign object.

Fix:confirm three-phase voltage ≥ 90%of rated;rewind if insulation<2 MΩ;hand-turn shaft,clear debris and replace bearing.

2.Loss of vibration/sudden amplitude drop

Root causes:eccentric weights mis-aligned;weight bolts loose;belt or coupling slip.

Fix:align both eccentrics to the same index(± 2°);torque bolts to spec(M12 ≈ 60 N·m);inspect drive elements and replace worn parts.

3.Abnormal noise hot frame

Root causes:bearing dry or clearance>0.15 mm;loose foot bolts;weak base.

Fix:re-grease or replace bearing;tighten foot bolts diagonally in three stages,re-check if torque drops>20%;add gusset plates if frame thickness<8 mm.

4.Over-temperature trip

Root causes:continuous overload;clogged cooling slots;missing phase.

Fix:keep current ≤ name-plate value;blow slots with 0.4 MPa air every two weeks;install phase-loss relay.

5.Current swings/erratic speed

Root causes:incorrect VFD settings;pitted contactor contacts.

Fix:set V/F mode,6 kHz carrier,150%start torque;clean or replace contacts until resistance<50 mΩ.

6.Low insulation resistance(<2 MΩ)

Root causes:moisture;conductive dust.

Fix:bake windings 8 h@110 °C and re-varnish;fit IP65 cover in dusty areas.

7.Cyclic bolt breakage

Root causes:no locking device;misalignment.

Fix:use 8.8 grade bolts,double nut Loctite 243;laser-align to within 0.2 mm parallel offset.

Daily“golden”rules

-Each shift:IR bearing temp ≤ 75 °C;housing vibration ≤ 6.3 mm/s.

-Weekly:re-torque all fasteners.

-Monthly:megger test&re-grease.

-Yearly:field balance to grade G 2.5.

Follow this routine to cut failures by>70%and double motor life.