Motor with the choice of circuit breaker

electric induction motor fan blade for ac motor 

Specifications
1. 20 years manufacturing experience 
2. competitive price,high quality

3. Delivery Detail:within 10 days after receiving deposit
Low voltage circuit breaker is generally divided into plastic shell type (also known as the device type) and frame type (also called universal type) two kinds big. The motor under 380 v245kw and more choose molded case circuit lamination machine breaker. Circuit breaker can be divided into the distribution line protection www.dongfeng- motor.com according to the use and protection, lighting protection circuit of the motor and electric leakage protection use and so on. Motor protection circuit breaker selection principles: (1) the set values for the long time delay current is equal to the rated current of the motor. (2) the instantaneous current setting: for the protection of cage motor circuit breaker, the adjusting current instantaneous equal to 8 to 15 times the rated current of the motor, rotor and stator depending on single phase motor the protected cage motor model, capacity and starting conditions. 

Alibaba China Suppliers!!Export aluminum electric motor casing 
Specifications
1. a replace of Y motor 
2. larger output 
3. save energy 

4. Delivery Detail:within 30-35 days after receiving the deposit
For wound rotor motor protection circuit breaker, the adjusting current instantaneous is equal to (3 acmotor2.blogspot.com ~ 6) times the rated current magnetic generator of the motor, depending on the protected wound rotor motor model, capacity and starting conditions. (3) 6 times of long time delay current setting value can return time is greater than or equal to the ac motors starting time of the motor. According to the weight of the starting load, can choose to return time 1 s, 3 s, generator 5 s, one of an 8 s, 15 s. Circuit breaker tripping device setting ac synchronous generator current simplified formula: "instant-on, motor kw 20 times" "thermal trip, according to the rating of the above formula is to protect a 380 v control of three-phase cage type motor circuit breakers, instantaneous motion setting its electromagnetic tripping current, according to the number of" kw "20 times". For thermal trip, according to the rated current of the motor selection.

The working principle of the pump and fan - screw pump

Screw pump is a kind of using screw pitch rotary pump suction and discharge the electric vehicle motor liquid. Screw pump rotor by active screw l (can be a root, also can have two or three) and driven screw ac electric motor 2. Driving screw and driven screw do turn in the opposite direction, thread pitch, fluid from inlet to be screw axis forward pressurization to discharge. This pump is applicable to high acmotortrading.blogspot.com pressure, small flow. Refrigeration system normally used for transport and the speed of oil pump bearing grease.

Motor current and battery current

 AC motor aluminum 2800 rpm motor fan cover 
Specifications
1. Customised 
2. good quality 
3. Surface treatment: Galvanize 
4. AC motor 
Using PWM technology speed of brush the power circuit of the controller. Would like to point out, brushless controller in a pair of upper and lower power tube conduction during the work, 3 phase induction motor also can get a form as a power circuit. So, the following discussion is based on figure 1, but the conclusion is also applicable to brushless diesel engine controller. According to different grid input signal, the power tube T there are three kinds of working state: 1. Fully closed. The Water pump motor does not turn, the battery current value is very small, weak current supply controller circuit. If ignore the weak current circuit power (for convenience, this hypothesis through the full text), motor and battery current and can be thought of as zero. 2. Complete conduction. The battery current flows through the motor, again through the power tube into the ground. Battery current and the motor current and power tube current are equal, all are smooth continuous dc current. Generally, transfer electric vehicle speed moving when the voltage spin to maximum, is this kind of situation. Ignore the power tube conduction pressure drop 3 phase induction motor equal to the motor directly to the battery. Electric characteristics is completely determined by the characteristics of the motor at this moment, has nothing to do with the controller. 3. The switch (chopped). Cycle the power tube grid input is the same, duty ratio control of variable pulse, three single phase motor phase induction motor so the squirrel cage induction motor power tube will continue in the open and disconnect between two states. 


Cast iron ac induction electric fan motor parts 

Specifications
1. 20 years manufacturing experience 
2. competitive price,high quality 

3. Type: iron body of AC electric motor 
Opening period, regardless of the opening of the transient current, battery current and the motor current and the instantaneous www.dongfeng-motor.com value of power tube current is equal; After disconnection, power tube current and battery current is zero. So, the battery current is pulsed current. And motor current situation is: power tube broken moment, according to Faraday's law of electromagnetic induction, the motor coil will produce self-induced electromotive force, its direction is by power tube end is positive, a negative side on batteries. As a result of the existence of stream tube D, to form a closed loop, the induced current. This process is a process of the original release of stored energy in the coil, the induced current will decrease over time until the next opening time of power tube. In other words, shut off during the current is induced current in the motor, it flows through the ac synchronous generator stream tube D, energy consumption in the motor coil resistance and flow pipe. Usually motor electromagnetic time constant is usually greater than the control pulse cycle, so shut off during the motor current will not reduce to zero. To sum up, said the battery are always equal, and the power tube current and battery and motor current in power tube only completely conduction is equal, in the state of chopper is not equal. During the chopper, battery is pulsed current, and the motor current is continuous, the former average average is less than the latter, and its size and the control of the conduction of pulse related to system parameters. The next section will give the relation between them.

Squirrel-cage asynchronous motor soft starter application - soft starter way of starting

electric motor 20hp aluminum body
Specifications
1.AC motor aluminum body
2.customized
3. 20 years manufacturing experience
4. competitive price,high quality

1 current-limiting starting: in the process of starting, limit the starting current does not exceed a certain value (Im), and then keep the output current, I < Im increased under the condition of voltage, until the rated voltage; The motor speed gradually increases, until the rated speed. Slope voltage starting 2: electric motor 12v 500w in electric vehicle motor the process of starting, the output torque of the motor with the increase of voltage, when starting to provide an initial starting voltage Us, then the output voltage from the Us started to grow in a certain slope, slope adjustable), motor accelerating. When the output voltage reaches up to Ur speed voltage, the motor is basically reach the rated speed. When the motor reaches the rated speed, make the output voltage at rated voltage. 3 starting torque control: use in overloading starting torque control, it is the starting torque of the motor from small to large linear rise. 


Y2 series electric motor wholesale

Specifications
1. effiency: IE2 and IE1
2. 20 years manufacturing experience
3. 12 months guarantee

4. low noise and vibtration

It has the advantage of smooth starting, flexibility is good, have better protection to drag system, its purpose is to protect the drag system, extend the service life of the drag system. 4 starting torque and kick control: at the beginning of the start stage, let the thyristor within a very short time conduction after all fall, according to the original set the value of the linear rise again, enter the starting with constant current. Starting torque and kick control and torque control starting similar is also used in overloading starting, the difference is with acmotortrading.blogspot.com a sudden jump in starting torque to overcome static torque of the motor, then smooth torque rise, shorten the start-up time. Starting: 5 voltage control the voltage control starting is used for light load starting of occasions, in guarantee starting pressure drop the maximum starting torque motor, as much as possible to shorten the start-up time, is the optimal way of light load soft starter.