User Manual Owner's manual

12 AC Induction Motors
Motor vibrates Motor misaligned Realign.
Weak support Strengthen base
Coupling out of balance Balance coupling.
Driven equipment unbalanced Rebalance driven equipment.
Defective bearings Replace bearing.
Bearings not in line Line up properly.
Balancing weights shifted Rebalance motor.
Polyphase motor running single phase Check for open circuit.
Excessive end play Adjust bearing or add shim.
Unbalanced line current on
polyphase motors during
normal operation
Unequal terminal volts Check leads and connections.
Single phase operation Check for open contacts.
Unbalanced voltage Correct unbalanced power supply.
Scraping noise Fan rubbing air shield Remove interference.
Fan striking insulation Clear fan.
Loose on bedplate Tighten holding bolts.
Noisy operation Airgap not uniform Check and correct bracket fits or bearing.
Rotor unbalance Rebalance.
Hot bearings general Bent or sprung shaft Straighten or replace shaft.
Excessive belt pull Decrease belt tension.
Pulleys too far away Move pulley closer to motor bearing.
Pulley diameter too small. Use larger pulleys.
Misalignment Correct by realignment of drive.
Hot bearings ball Insufficient grease Maintain proper quantity of grease in bearing.
Deterioration of grease or lubricant
contaminated
Remove old grease, wash bearings thoroughly in kerosene and replace
with new grease.
Excess lubricant Reduce quantity of grease, bearing should not be more than 1/2 filled.
Overloaded bearing Check alignment, side and end thrust.
Broken ball or rough races Replace bearing, first clean housing thoroughly.
Trouble Cause What To Do