Three-phase asynchronous motor winding short circuit

Due to poor welding or use corrosive flux,have not cleared after welding,it may cause a pot of welding or loose;Subjected to mechanical stress or collision coil short circuit,also can make the wire burned,short circuit and earth fault in a couple of wire and burn a single or a few wire short circuit,several other wire due to the increase of current temperature rise,cause heating winding and open circuit.Generally fall into one phase winding end disconnection,turn-to-turn short circuit,parallel branch circuit,wire and burn more of a single circuit,rotor broken cage.Fault phenomenon: 1.The motor can't start,unbalanced three phase current,there are abnormal noise or vibration,temperature rise more than permitted or smoke.2.Reasons: (1) during overhaul and maintenance touch off or manufacturing quality problems.,(2) winding each element (phase) group and the 5kw permanent magnet generator winding and fixture wire connection head welding,sealing off long running overheating.(3) by the mechanical force and electromagnetic force make winding damage or pulled apart or cause drag mark.(4) or interphase short circuit and grounding caused winding coils badly burned or fuse,etc.

3.Check the method: (1) the method of observation.Breakpoint most occurred in winding ends,look have without touch fold,joint the presence of desoldering.(2) a multimeter.Using resistance,to "Y" type of connection to connect a table bar in the center of the "Y" shape,the other in turn in the head end of the electric motors price three-phase winding,infinite phase has a breakpoint;"Delta" connection type of short connection,measuring winding in each group respectively,infinity to breaking point.(3) test lamp.Method with former,such as bright a photograph for open circuit.(4) megohmmeter.Resistance tends to infinity (that is,not as a zero value) is the cut-off point.(5) current meter method.Motor at runtime,use current meter to measure three phase current,if the imbalance of three phase current and short-circuit phenomenon,and no is a phase winding is part of the current small short circuit fault.(6) bridge method.A phase when the motor is bigger than the other two phase resistance,resistance show that the phase winding part of open circuit fault;(7) the current balance method.For "Y" type of connection,but after the three-phase winding parallel,alternating current into the low voltage large current,if the current in the three-phase winding is greater than 10%,one end of the small current for the circuit;For "delta" connection type,the stator winding of a contact apart first,then by interlinked into low voltage high current,wholesalemotor.blogspot.com one of the small current for open circuit.(8) broken cage detector test.Check,if the broken rotor cage millivoltmeter readings should be reduced.

4.Open circuit processing method: (1) open circuit in the end,the connection after welded,set of insulating tube,with insulation material and good binding,dry again.(2) the winding due to interturn,interphase short circuit and grounding,etc and cause severe charred generally should change new windings.(3) to the breaking point in the slot,belong to a few breakpoints for single phase asynchronous motor emergency treatment,the grouping elimination method is adopted to find the breakpoint,and broken in winding connection and the insulation used after qualified.(4) can be used for broken squirrel-cage rotor cage welding,cold connection or change the original repair.

Cascade speed regulation method

Cascade speed regulation refers to the motor rotor winding circuit in series motor vehicle spare partswith adjustable additional potential to change the slip of the motor,to achieve the purpose of speed control.Most of the slip power is absorbed by series of additional potential to recycle produce additional device,the absorption of 12 volt electric motor returning the slip power grid or conversion of energy use.According to the slip power utilization way,cascade speed regulation can be divided wholesalemotor.blogspot.com into motor cascade speed regulation,mechanical cascade speed regulation and thyristor cascade speed regulation form,adopts thyristor cascade speed regulation electrical motor.

 Its characteristic is: to speed the slip loss in the process of feedback to the grid or production machinery,high efficiency;Installed capacity is proportional to the speed range,the investment province,apply to speed range in production machinery from 70% to 90% of the rated speed;Speed regulating device failure can switch to run at full speed,avoid production;Thyristor cascade speed regulating power factor is low,the influence on harmonic.This method is suitable for the fan,water pump and the rolling mill,mine hoist,the extrusion machine use.

The common malfunction and expel the three-phase asynchronous motor

Pick to:People's Daily life cannot leave the use of the motor,the production,220v ac electric motors in the using process of www.dongfeng-motor.com the motor has a lot of attention and requirements,may cause significant safety accident.Therefore,how to timely diagnosis permanent magnet motors for sale and troubleshooting,prevent accidents,ensure the safe,reliable and efficient operation of motor,is particularly important for enterprises.Motor fault types,is more complex,can be summarized as two aspects of mechanical and rotor and stator electrical,machinery has swept

chamber,vibration,overheating and damage to the bearing fault; Electrical failure of the stator

windings without phase operation,the reverse of the stator winding unbalanced three phase

current,short-circuit and ground heating winding and rotor winding fault,open circuit,etc.The

analysis in this paper,the commonly used motor fault problems,some one motor fault diagnosis and

maintenance and repair measures.

Motor model significance

Y series three phase asynchronous motor is totally enclosed fan since air-cooled squirrel-cage ac asynchronous motor,it is the latest series of uniform design in our country,the protective class is IP44.Y series motor with high efficiency,energy saving,large starting torque,good performance,low noise,small vibration,high reliability,power rating and installation size and conform to the IEC standards Use acmotortrading.blogspot.com convenient maintenance.Y series motors are suitable for excluding inflammable,explosive or corrosive gas general places and no special requirements of mechanical,such as:metal cutting Cutting machine,water pump,blower,transport machinery,mixers,agricultural machinery,food machinery,etc.Y series motor model consists of four parts:the first part of Chinese Phonetic alphabet Y said asynchronous motor; Second part Numbers stand center high (stand without a foot,and stand with when the generator rotor and stator foot is the

same).The third part of the English letters For the frame length codes (S - short stand,stand in the

M -,L - lead),letter after the digital code for the core length; Conditions of use ambient

temperature:no more than 40 ℃.Altitude:not more than 1000 meters.Relative humidity:less than 95 ℅

rated voltage:380 v.:rated frequency 50 hz.Connection:3 kw and the following to Y,4 kw and to For

answered.Work style:continuous (S1).Example models:Y132S1-2 3 kw Y.Y said asynchronous motor 132.The second part of the figures show that the frame Center high millimeters (stand without a foot,and

stand with when the foot is the same).S -.The third part of the English letters stand length codes (S

- short frame,the M - Stand,L - lead),letter after the number for the length of the core code; 1

-.Letter after the number for the core code length; - 2.The fourth part after the dash Figures for

the number of motor,this is a 2 pole motor.3 kw motor power of digital,said this is a complete

machine model.2 the meaning of Y132S1 - Righteousness is:the number of series number + base + The

first part of the Chinese phonetic 6v electric motor alphabet Y said asynchronous motor; The second part Numbers stand center high (stand without a foot, And to the same frame with foot); The third part of the English letters stand length codes (S - short stand,stand,L - the length of the M -),letter after the number for the core length Code; Conditions of use ambient temperature:no more than 40 ℃.Altitude:not more than 1000 meters.Relative humidity:less than 95 ℅ rated voltage:380 v.:rated frequency 50 hz.Connection:3 kw and the following to Y,4 mw and above for answered.Work style:continuous (S1).