The cause of the motor open phase have?

Power supply:(1) the switch contact undesirable;(2) transformer or line break;(3) the safety

fuse.Motor:(1) motor terminal box screw loose poor contact;(2) the internal wiring bad welding;(3)

the motor winding wire break.What are the induction motor sales causes of abnormal vibration and sound? Mechanical aspects:(1) poor lubrication bearing,bearing wear;(2) bearing chamber www.dongfeng-motor.com is too large.(3) fastening screw loose;(4) motor with sundry.Electromagnetic aspects:(1) the motor overload operation;(2) three phase current balance;(3) lack of phase,(4) of the stator,rotor winding short- circuit fault;(5) caused by the welding part of the open welding of cage rotor broken bar.What are the cause of the motor bearing overheating?

The motor itself:(1) the bearing inner and outer ring with tight;(2) parts shape tolerance has a problem,such as frame,end cover,shaft parts alignment is bad; (3) bearing improper selection;(4) bearing or bearing cleaning not net,poor lubrication grease with sundry;(5) the shaft current.Use: pumps (1) improper installation,such as the motor shaft and the drive device of the shaft alignment of undesirable;(2) pulley pulled too tight; (3) bearing bad maintenance,insufficient or grease,could more than dry deterioration.The motor insulation resistance low what are the reasons?(1) winding be affected with damp be affected with damp or water invasion;(2) winding on accumulation of dust or oil;(3) insulation aging;(4) motor wire or wiring board insulation damage.