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generator Stator Rotor 

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

3. Accessories Series: stator and rotor 
 (1), back bandwidth, exchange of two/three layer throughput. This determines the actual performance of the network, regardless of the switch function, more management more convenient, if the actual throughput, the network will only become overcrowded. So these three parameters is one of the most important. Bandwidth backplane includes ac electric motor exchange between the switch port, port and switch inside the bandwidth data exchange and internal system data exchange. Layer 2/3 switching throughput performance of two/three layer exchange actual throughput, the throughput should be greater than or equal to switch ∑ (ports (bandwidth). (2), VLAN type and amount, a switch to support more VLAN type and quantity will be more convenient for the design and implementation of network topology. (3), TRUNKING, current switches support this feature, and also not too widely in practical application, so people think that as long as the support this function, how many lines are not required to provide maximum binding. (4), switch port number and type, different applications have different needs, depending on the specific magnet generator situation. (5), support network management protocol and methods. Need to switch to provide more convenient and centralized management.


AC Electric motor Plastic fan parts 

Specifications
1. Customised 
2. good quality 
3. 20 years manufacturing experience 

4. Delivery Detail: 20-35 days after receiving payment 
 (6) priority control, Qos, 802.1 q, 802.1 X, 802.3 X support, these are all switches the direction of development, these functions can provide better network traffic control and user management, procurement support these function switches should be considered. (7), stack, as users increase, the stack, it is very important. General corporate expansion method of switch port connection points for a main switch the port switch, this switch and main switch maximum data transfer rate is only 100 m, greatly influenced the exchange of performance, if we can adopt the stacking mode, its in G bandwidth will play a huge role. Main parameters are stacked number stack, stack method, bandwidth, etc. (8), switches, and the exchange of cache cache, main memory, and port forwarding delay is also quite important parameters, such as. (9), for layer 3 switches, 802.1 d production is also an important parameter in the tree, this function can let the Single phase motor switch to the network structure, learning on the performance of the network also has a lot of help. (10), layer 3 switches and some important parameters, such as launch other function whether two/three keep wire-speed forwarding, routing table size, and the size of the access control list, right by the protocol support, support for multicast protocol, packet filtering method, the machine ability to scale is worth considering the parameters, such as, should according to the actual situation.

The role of current transformer, current transformer

 generator Stator Rotor 
Specifications
1. 20 years manufacturing experience
2. competitive price,high quality
3. Accessories Series: stator and rotor
 Can the function of current transformer is the numerical larger current through a variable than convert numerical smaller secondary current, used for protection, measurement and other purposes. If change ratio of 400/5 of the current transformer, which can transform the actual for 400 a current of 5 a current. 1 principle of selection and inspection of current transformer) current transformers rated voltage is not less than the rated voltage instruction in line; 2) a load calculation according to the current IC choose current transformer changes; 3) choose according to the requirements of the secondary loop current transformer accuracy and calibration accuracy; 4) check dynamic stability and thermal stability. 


Totally Enclosed Protect Feature and Three-phase Phase low rpm ac electric motor

Specifications
power range: 0.12-18.5 kW 
Centre height of frame: 63-160 mm 
Rated Voltage: 380 V 

Rated Frequency: 50Hz or 60Hz 
2 current transformer converter than choice. Current transformer is a rated current I1n and the ratio of the secondary rated current I2n, called a current transformer rated current transformer ratio, Ki = I1n/I2n material N2 / N1. Type, N1 and N2 for current transformer primary winding and secondary winding turns. Current transformer primary side than rated current standard (e.g., 20, 30, 40, 50, 75, 100, 75, 2 (A) xa/C) wait for A variety of specifications, the secondary side current rating is usually 1 A or 5 A. Says the same two xa/C products have two kinds of current ratio, by changing the product at the top of the oil storage tank outside the connector wiring way, when the series current ratio of a/C, parallel 3 phase induction motor current ratio of 2 xa/C. In general, the choice of measurement with ct (current transformer) current transformer ratio should make one times rated current I1n not less than the load current in a circuit (IC). Such as load calculation in Induction motor line current is 350 a, the converter of current transformer ratio ac fan motor should choose 400/5. Protect with current transformer to ensure its accuracy requirement, can be changed than done.

The working principle of the ac contactor

Electromagnetic suction when energized coil,the static iron core,will be moving iron core and,as a result of the contact system is with the linkage of moving iron core,so core to drive three move contact run at the single phase electric motor same time,the contact closure,and connected to the power supply.Disappear when power coil,suction,moving iron core linkage part rely on spring reaction and separation,make the main contactor disconnect,cut off power supply.The choice of ac contactor:(1) the continuous operation of equipment.Contactor calculate by 67-75%.The 100 - a ac contactor,can control the maximum rated current is 67-75 - a the following equipment.(2) uninterrupted operation of equipment.Contactor calculate by 80%.The 100 - a ac contactor,can only control the maximum rated current is 80 a the following equipment.(3) and short- time working equipment.Contactor calculate by 116-120%.


The 100 a ac contactor,can only control the maximum rated current is below 116-120 - a device.Consider the work environment electric motors 12 volt and the structure of contactor.Also shows that:as the market competition is intense,to reduce the cost of domestic some manufacturer,has been in the corners,for example:in the coil production reduce wire diameter less number of turns around,even in touch head is not in conformity with the national standard of the material or thickness and the cross section is not ac electric motors enough.This kind of circumstance is not only reflected in the contactor,on top of other products such as short as well.Cause in be used actually,mark is 100 a contactor or short circuit,the actual load can only be even lower in 80 a,high failure rate.Popular theory is:so,now have to use domestic low-end products,to the rated capacity of 7 discount according to the www.facebook.com/dongfeng.motor nameplate instruction to use!

Measuring rotor winding connection is wrong use method of failure

 Put the rotor under small electric fan motor test in a test in the mouth,use the turn-to-turn short circuit tester electricity,tester within the closed magnetic circuit core and rotor core has alternating magnetic flux.Multimeter is 10 v ac voltage profile,wholesalemotor.blogspot.com adjacent commutator segment and commutator segment,every piece of commutator segment,every two pieces of commutator segment,every three to every more pieces commutator segment between the voltage value.Rotor winding connection correct voltage size should electricalmotor1.blogspot.com be consistent,if you have below normal,it is possible that some components lead to reverse,with the fault of rotor winding to repair to meet again. "Little experience" Described above with a multimeter ac 10 v voltage profile measuring voltage between adjacent the commutator segment,as there are below normal,should turn the rotor position,and then look at the voltage value,so as high efficiency electric motor to avoid miscalculation.If still below normal,should be cleaned of mica slot commutator conductive material (such as charcoal powder),then test again,in order to avoid miscalculation.

The cause of the motor open phase have?

Power supply:(1) the switch contact undesirable;(2) transformer or line break;(3) the safety

fuse.Motor:(1) motor terminal box screw loose poor contact;(2) the internal wiring bad welding;(3)

the motor winding wire break.What are the induction motor sales causes of abnormal vibration and sound? Mechanical aspects:(1) poor lubrication bearing,bearing wear;(2) bearing chamber www.dongfeng-motor.com is too large.(3) fastening screw loose;(4) motor with sundry.Electromagnetic aspects:(1) the motor overload operation;(2) three phase current balance;(3) lack of phase,(4) of the stator,rotor winding short- circuit fault;(5) caused by the welding part of the open welding of cage rotor broken bar.What are the cause of the motor bearing overheating?

The motor itself:(1) the bearing inner and outer ring with tight;(2) parts shape tolerance has a problem,such as frame,end cover,shaft parts alignment is bad; (3) bearing improper selection;(4) bearing or bearing cleaning not net,poor lubrication grease with sundry;(5) the shaft current.Use: pumps (1) improper installation,such as the motor shaft and the drive device of the shaft alignment of undesirable;(2) pulley pulled too tight; (3) bearing bad maintenance,insufficient or grease,could more than dry deterioration.The motor insulation resistance low what are the reasons?(1) winding be affected with damp be affected with damp or water invasion;(2) winding on accumulation of dust or oil;(3) insulation aging;(4) motor wire or wiring board insulation damage.

Electrician training of motor working principle and the composition of the work

A. the motor operation of work: Now more commonly used mainly by ac motor, it can be divided into three phase asynchronous motor, single phase ac motor, two of the former is more used in industry, and then a usually used in civil electrical appliances. Look from the structure of the motor, mainly divided into the control part and execute drive part and control part is mainly composed of three-phase PWM www.facebook.com/dongfeng.motor wave generator, single chip microcomputer, intelligent inverter, rectifier module, A/D module, fault detection, input and output channels, etc; Perform drive part mainly includes the three-phase motor and position sensor bar. B. the working principle of the machine Motor operation is working on the current and voltage motor part sensor and position sensor detection, draw A three-phase inverter module output current, voltage and the valve position signal, and then magnet generator by the A/D converted into single chip microcomputer. Single-chip microcomputer by controlling the effect of PWM wave generator, finally realize the operation control of the machine. Inverter modules work required by the rectifier circuit dc voltage signal to the whole bridge rectifier of 380 v power supply. For the analysis of the motor running, here mainly for industrial application of the principle of three phase asynchronous motor are discussed. Motor rotation is the basic working principle of the three-phase symmetric winding zhongtong people produce round rotating magnetic field, the three-phase current conductor cutting rotor rotating magnetic field induction electromotive force and the current, the rotor current carrying conductor in magnetic field by electromagnetic force, thus forming the electromagnetic torque, driving the motor rotor rotation.