Winding is part and parcel of the motors,aging,be affected with damp be affected with damp,heat,erosion,foreign bodies,intrusion,the impact of the external force can cause damage to
winding,motor overload,under voltage,over voltage,lack of phase operation can also cause winding
fault.Winding grounding,short circuit,open circuit fault generally fall into winding,connection errors.Now separately failure phenomena,causes and inspection method.A,winding grounding Refers to the winding and iron core or with insulation casing damage caused by the grounding.1,failure phenomenon Chassis charged,heat control circuit is out of control,winding short circuit,the normal operation of the motor.2,the reason Winding insulation resistance decreased,motor overload long-term operation of be affected with damp be affected with damp,harmful gas corrosion,metal foreign body into internal damage to the wholesalemotor.blogspot.com insulation,rewind stator windings insulation when damage to core,winding end touch end cover frame,stator rotor friction cause burns,lead insulation insulation damage and shell,and overvoltage (such as lightning) insulation breakdown.Methods to examine 3.(1) the method of observation.
Through visual winding overhang and line
slot insulation observed with and without damage and charred traces,is the pick up location.(2) the multimeter test.The multimeter low-resistance archives check,reading is very small,it is grounded.(3) megohmmeter.Selected according to different levels of different measuring each group resistance of insulation resistance by megger are,if the reading is zero,then the winding grounding,but the motor insulation be affected with damp be affected with damp or breakdown due to accident,must determine on the basis of experience,generally pointer swing timing in "0" place,its have certain resistance value can be thought of.(4) water pump motor try to light.If try lights,winding grounding,if found somewhere with a spark or smoke,is the place for winding grounding fault point.If lights dim the insulated grounding breakdown.If the light is not bright,but also showed a spark when the test stick ground,winding yet breakdown,just seriously be affected with damp be affected with damp.Also can use hardwood on the edge of the shell of the seam allowance tapping,to a certain place when a out a bright,when electrical current when broken,it is ground.
(5) current wear burning www.facebook.com/guohong.trading method.With a regulating transformer,after the power is connected,ground quickly small electric motors heating and insulation smoke is the pick up location.Should pay special attention to small motor shall not be more than twice the
rated current,no more than half a minute,large motor as 20% - 20% of rated current or increasing
current,burning to the ground just immediately without electricity.(6) packet elimination method.For
the pick up location in iron core and burning more severe,in my heart burning loss of copper and iron
core melt together.Approach is to put the grounding of one phase winding is divided into two and a
half,and so on,finally find out the ground.In addition,there is high pressure test method,magnetic
exploration method,power frequency vibration method,etc.4.The processing method (1) winding drying should be affected with damp be affected with damp cause ground,when cooled to about 60-70 ℃,pour insulating paint again after drying.(2) the end winding insulation damage,on the insulation
processing is located in the back,painted and drying.(3) windings to place in the groove,should
rewind or replace part windings components.Finally apply different measured by megger,meet the
technical requirements.
