Why low voltage winding of transformer in the inside,and high voltage winding in the outside?

 The arrangement of the high and acmotor2.blogspot.com low voltage transformer,it is decided by many factors.But for most of the transformer,low level around the layout in the high voltage winding is put inside.This is mainly from the insulation into consideration.In theory,no matter how high or low voltage windings to decorate,can be variable pressure role.But because the iron core transformer is grounded,due to the single phase generator low voltage winding is close to the core,from the perspective of insulation easy to do.If the high voltage winding is close to the core,is due to the high voltage winding voltage is very high,to meet the insulation requirements,requires very of insulation materials and the insulation of the large distance.Such not only increases the volume of small electric motors the winding,and waste of the insulating material.Moreover,as a result of the transformer voltage regulation is electrical motor to rely on change of the high voltage winding tap,namely change the number of turns,so the high voltage winding is placed in the low voltage winding outside,lead more easily also.

Pump and fan - displacement

Pump and fan is to use plus can denier conveying fluid fluid machinery. They are widely used in gas and heating and ventilation. According to the working principle of pump and fan, usually they electrical motor can be classified asynchronous motor as follows: Positive displacement pump and fan in operation, the mechanical work within the volume change constantly, and motor run capacitor suction or discharge fluid. According to its different structures, and can be divided into; 1. Reciprocating: this machine through the piston within the cylinder of the reciprocating function make the cylinder contents changed repeatedly, with suction and discharge fluid, such as piston pump, piston pump), etc.; 2. Rotary: chassis within the rotor rotates, or rotating parts working volume change between rotor acmotortrading.blogspot.com and housing, so as to the suction and discharge fluid, such as gear pump, gear pump), screw pump, screw pump), etc.

Motor can't start

1,motor does not turn and there is no sound: more than two phase or two phase power or winding circuit,first check the power supply voltage,if the balance of three-phase voltage,then fault in the motor itself,can detect the resistance of the three-phase winding of single phase capacitor

start induction motorthe motor,to find out the wire diesel generator winding.And 2,the motor does not turn but hum: measuring the motor terminal,if the balance of three phase voltage and rated voltage value,can judgment is serious overload,check the steps of: first take the load,then the speed of the motor with a normal voice,which can determine overload or load malfunction with the mechanical parts,if still won't turn,twist of the hand motor shaft are available,and if it is tight or motionless,and three phase current,if the three phase current balance,but larger than the rating,the mechanical part of the motor was stuck,may lack of oil motor,bearing rust,or was badly damaged and end cover or oil cover too oblique,rotor and bore a collision sweep (bore) when turn the motor shaft by hand to feel struggled with a certain way or heard diesel generator periodically wiping,the chamber can be judged to sweep.

3,,the motor speed slowly and have a buzz: this kind of failure of shaft cooperates,if measured one phase current is zero,while the other two phase current is far higher than the rated current,that is two phase operation,and the reason is: circuit or power supply circuit,a phase or a motor winding circuit. Whether the small capacity of the motor can be measured with a multimeter direct on and off. Medium capacity motor use much more due to winding wire and around many branch in parallel,which if broken several root or disconnect a parallel branch check up more troublesome,when such a situation usually adopts the method of phase current balance or resistance method. Use a bridge measuring the resistance of the three-phase winding resistance method,such as three-phase resistance percentage www.dongfeng-motor.com difference five above,a phase for breaking phase resistance is larger.

motor

Motor (Motors) is a device converts electrical energy into mechanical energy.It is using electric coil (that is,the stator winding) to produce a rotating magnetic motor spare parts field and try to turn the mouse cage closed wholesalemotor.blogspot.com form magnetic aluminum frame Electric rotary torque.Motor by using the power divided into dc motor and ac motor,electric power system www.dongfeng-motor.com in most of the motor is ac motor,synchronous motor or induction motor (speed and the rotor rotating speed of stator magnetic field is not in sync speed).Motor is mainly composed of stator and rotor,the direction of motion of the wire in the magnetic field force with the motor lamination direction of current and magnetic induction line (magnetic Field direction) direction.Working principle of the motor is a function of magnetic field on the current stress,to rotate the motor.

Y series three phase asynchronous motor

Structure design,main is also considering the non-sinusoidal power characteristics of variable

frequency motor insulation structure,the industrial fan motors electric influence of vibration and noise

cooling mode,generally pay attention to the following questions:1) the insulation class,generally for F or higher,strengthen the insulation and line turn insulation strength,especially want to consider

the ability of impact resistance voltage insulation.2) to the problem of vibration and noise of the motor,the motor should be fully considered component and overall rigidity,trying to improve its natural frequency,in order to avoid and every force wave resonance phenomenon.3) cooling way:general

using forced air cooling,or main Y series three-phase asynchronous motor cooling fan wholesalemotor.blogspot.com with independent

motor drive.4) measures to prevent shaft current,the capacity of more than 160 kw motor bearing

insulation measures should be adopted. Mainly produces magnetic circuit asymmetry,also can produce shaft current,while the rest of the high frequency component generated by the current role in combination,shaft current will increase greatly,which can lead to bearing damage,so often insulation measures.5) to motor fan the constant power variable frequency motor,when the rotation speed of more than 3000 / min,high temperature resistant special grease should be adopted,to compensate for the temperature of the bearing.