(1) motor can't start motor starting,ringing or low speed,this is the most common fault.Its reason is: power disconnection or blown fuse,switch starting equipment or a poor contact or broken line in the stator coil;Or because of lag in the brush brush card,no contact with the slip ring;Stator voltage is too low or excessive load on the reason leads to the failure.Processing methods available voltmeter to check voltage of the motor,such as a phase power lines to check the power supply of power,insurance,switch and starting equipment contact,repair or update processing respectively.If starting rheostat is damaged,can be used to check the lamp or shaking table test,find out the fault repair;If it is found that the load is too big,should reduce or change the capacity of the larger motor. (2) motor overheating causes overload or stator terminal voltage is too high,too low,poor ventilation,may also electric motor have a bolt stator coil,etc.Measures should be
taken,such as reducing load,to adjust the mechanical and electrical pressure rating,remove the body
ventilation slot dirties dustiness,bolt repair .
(3) the spark to appear on the slide Reason is lack of
the pressure on the slip ring or carbon brush and slip ring dirt,etc.,can be used sand paper to grind is good,with the cleaning brush frame,make the carbon brush block, perkins diesel generator adjust the spring pressure;Also can use clean cloth dipped in a small amount of gasoline,cleaning brush.If spark for slip ring is not round,can take fine car slip ring polishing. (4) motor violent vibration Reason to install more bad,single phase asynchronous motor basic not firm,foot screw is not tight;The individual may also be due to rotor copper bar tensile fracture or short circuit ring.Find out that the former should be correct,which can
replace the new copper,the fracture of the available copper weld repair.Sometimes because the
rotational part touching the fixed place.Should check the shaft wear and clearance of the stator and rotor,take the fine car rotor or replacement of wearing parts. (5) motor no-load current balance,but value is big .
1.The cause of the problem (1) to repair,the stator winding turns to reduce too much;(2)
power supply voltage is too high;(3) Y after motor misconnection ;(4) in the motor assembly,rotor
installed backwards,making the stator core unaligned,effective length cut short;(5) the air gap is
too large or uneven;6 overhaul when the demolition of the old winding,using hot tear open method is undeserved,make the iron core loss. 2.The troubleshooting (1) rewind stator winding,restore the correct number of turns;(2) managed to restore rated voltage;(3) to connect to Y;(4) the new rotor assembly (3) to replace or adjust the air gap;(5) maintenance core or recalculate winding,appropriately increase the number of turns.
A,the classification of the three-phase asynchronous motor:Classification:according to the rotor structure Category:squirrel-cage motor and wound rotor motor According to the protection type Categories:open (IP11),protected (IP22 and IP23),closed (IP44),explosion-proof According to the ventilation cooling way Categories:self-cooled,since fan cooled,he fan cooled,pipes,ventilated According to ac synchronous motor the installation structure Categories:horizontal,vertical foot,flange According to the grades of insulation Category:E,B,F,H, According to the work quota Category:continuous,intermittent,intermittent Description:Open (IP11) :cheaper price,the best cooling conditions,due to the rotor windings and exposed to air,can only be used for dry,little dust and no corrosive and explosive gas environment.Protected (IP22 and IP23) :ventilation cooling condition is good,also can prevent the water droplets and iron filings,sundry fall into motor internal,applies only to a few dry and dust and no corrosive and explosive gas environment.Enclosed (IP44) :suitable for damp,dusty,vulnerable to wind and rain erosion,corrosive gases,such as the poor working rotor and stator environment,the most common applications.
Second,the structure of the three-phase asynchronous motor (a) of the stator (static) 1,the stator core Part of motor magnetic circuit,and placed on the stator winding.Structure:the stator iron core by 0.35 ~ 0.5 mm thick surface is commonly insulating layer of silicon steel sheet coining,overlying and become,within the core of the circle has a uniform distribution trough,which embedded in the stator winding.Trough the stator core has the following kinds:Semi-closed type slot:frequency conversion motor efficiency and power factor is higher,but the winding wire and insulation are more difficult.Commonly used in low-voltage motor.Half-open mouth slot:can put molding winding embedded,commonly used in large and medium-sized low-voltage motors.The so-called forming the windings can be treated with insulation in advance and then into the slot.Open rack slot:to put molding winding embedded,insulation method is convenient,mainly used in high voltage motor.2,the stator winding Access is the circuit part of the motor,three-phase alternating current (ac),to produce a rotating magnetic field.Structure:by the three in the space between 120 ° Angle,said arrangement can be connected with the same structure of the winding,the winding of the coil respectively according to certain rule embedded in the stator slot.The main of the stator winding insulation project has the following three:(guarantee between the conductive part of the winding and iron core and reliable insulation and reliable insulation between the winding itself) (1) of insulation:overall between the stator core and stator winding insulation.(2) and white insulation:insulation between each phase of the stator winding.(3) the turn-to-turn insulation:each phase of the stator winding turn-to-turn insulation each wire.
