The role of voltage transformer and current transformer

The high voltage proportional relationship to transform the 100 v or lower level standard secondary voltage, for the use of protection, measurement and instrumentation. At the same time, the use of voltage transformer can be high voltage and electrical isolation. Although also be in accordance with the working principle of electromagnetic induction voltage transformer equipment, but its electromagnetic structure compared with the current transformer is just the opposite. Voltage transformer secondary circuit is high impedance circuit, the size of the secondary current is decided by the impedance of the loop. Secondary load impedance, small secondary current increase, makes a in a component of current automatically to meet electromagnetic balance of the relationship between the primary and secondary side. A voltage transformer is, as it were, structure and using a limited form of special transformer. Electromagnetic single phase motor current transformer is widely used in power system (hereinafter referred to as "current transformer"), its working principle is similar to the transformer. 


The principle of current transformer wiring, as shown on the left. The characteristics of the current transformer is: (1) a coil in series in the circuit, and as a result, the number of turns in a coil current depends on the load current of the circuit under test. And has nothing to do with the secondary current; (2) current transformer secondary coil of the current meter and relay to the coil impedance is 220v 1.5kw ac motor very small, so under normal circumstances, current transformer run in to a short-circuit condition. The ratio of the current transformer primary and secondary rated current, called the rated mutual acmotortrading.blogspot.com inductance of the current transformer ratio: kn = I1n/I2n Because of one coil rated current I1n standardization, secondary coil rated current I2n unification of 5 (1 or 0.5), so the rated mutual inductance current transformer ratio have also been standardized. Kn can be approximately expressed as transformer primary and secondary winding turn ratio, namely the kn material kn = N1 N2 / type of N1, N2, for one, two coil number of turns.

The starting current of the machine

 China export motor lamination shaft rotors 
Specifications
1. Lamination of electric motor 
2. IP54 class F 
3. 100% copper 
4. Silicon steel stamping 
5. Stunning performance
The motor starting current is www.facebook.com/guohong.trading not a fixed value, in the process of motor starting, from big to small changes in the current, is the reciprocal function of time (I diesel engine = I + I/(a - t)). There is no specific formula. diesel generator Basic not just plug in the electrical impedance, only impedance, also is the dc resistance of the coil, this number is very small, so the instantaneous current is very big, can be rated current of dozens of times, but the duration is very short, usually only zero point zero seconds. As the rotating motor, a sharp drop in the auto spare parts current, if not on load 3 phase induction motor startup, will be in 1 seconds to around 10 times the rated current, along with the speed rise, after 2 single phase motor seconds can be down to 2-3 times, then continue to fall, until it is equal to the rated current, the motor speed also rose to rated speed. 

TYG series rare permanent magnets three phase synchronous motor
Specifications
1. a replace of Y motor 
2. larger output 

3. save energy
So, motor starting current is refers to the average. Because different machine, different load and different ways of start, start time required is not the same, there is big difference between the average current. For large motor, you need to start the process of current time function for diesel generator set detailed calculation, to determine the circuit breaker protection fixed value setting. Generally small under 40 kw motor, is does not provide protection for the boot process, so the choice of circuit breaker, so long as can avoid starting current impact. Due to the action of circuit breaker is time-limited, 4 to 7 times the rated current, no-load start to choose lower limit, with maximum load startup options. The star - Angle start, start current 1.7 times lower magnetic generator than direct start, but the duration should be longer, switch to the Angle, the current changed little.

Motor wiring

 China export motor lamination shaft rotors 
Specifications
1. Lamination of electric motor 
2. IP54 class F 
3. 100% copper 
4. Silicon steel stamping 
5. Stunning performance
Motor wiring mantra: www.dongfeng-motor.com "1.5 plus two, plus three" 1.5 "after the four plus four, six plus six," "increasing after 25 plus five, after 50 minus five" 102 conductor, the best number "the mantra diesel engine is equipped with wire directly based on the three-phase 380 v ac motor capacity." 1.5 plus two "said 1.5 was copper, plastic wire, can go with 3.5 kW and the following motor. Because of the 4 kW motor selection of close to 3.5 kW use scope, and the formula has certain allowance, so the quick table 4 kW motor under the selected conductor take 1.5 was." After 2.5 plus three ", auto spare parts "four plus four", said was 3 phase induction motor 2.5 and 4 was the copper plastic wire to auto spare parts respectively 5.5 kW, 8 kW motor." After six plus six, "said from the beginning of the 6 was, with the" increase 6 kW motor. 


full load 75% load 50%load three phase induction electric motor Y series B35
Specifications
-One year warranty 
-Within 25 days delivery 

-Life: 5-7 years
"that squirrel cage induction motor was can match 12 kW, choose similar specification with 11 kW motor. 10 was 16 kW, choose similar specification with 15 kW motor. 16 was 22 kW acmotor2.blogspot.com motor can match. The middle and 18.5 kW motor, also copper plastic line 16 was chosen." After 25 plus five ", it is said from 25 was addend from six to five. 25 was 30 kw electric motor can match. 35 was 40 kw can match, choose similar diesel generator set specification with 37 kw motor." Increasing after 50 minus five ", it is said that since 50 was made up into a reduced, and it is increasing step by step to lose five. 50 was 45 kw motor can be produced (50-5). 70 was can match up to 60 kw (70-10), select similar specification is equipped with 55 kw electric motor. 95 was can match 80 kw (95-15), choose similar specification with 75 kw motor." 102 conductor, with the number ", magnetic generator it is said that 120 was the copper plastic wire can match 100 kw motor, phase selection specifications namely 90 kw electric motor.

DBJ08-20-98 household electric equipment should meet the following standard

Stator And Rotor ac induction motor parts 

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

3. Material: silicon steel 
13 and 3 phase induction motor grounded. Special ground wire (PE). In a setting into the diesel engine door of every building a set the ends of generator the earth and the connected line dish, the grounding resistance shall not be greater than 4. 14, lightning protection grounding and protection of the electric system is set up separately, lightning protection grounding auto spare parts resistance shall not be greater than 10. Talk single phase motor about it before, let's learn two basic formula for junior middle school physics: power = voltage by current; Copper core ac synchronous generator wire load voltage coefficient of x = x crosscutting ampere area (the coefficient of amps that should be roughly between about 5 ~ 10 amperes, about 10 in the single phase induction motor air, direct cement by death around 5, online pipe according to how much space between 6 ~ 8). Actually we decorate in the family in, basically open wire and circuit principle of www.facebook.com/guohong.trading distribution of big things come from these two basic physical formula, is very simple. Unfortunately, under our current market situation, more than 99% of all home electrical and magnetic generator decoration company materials manufacturers and habits to judge on the basis of the so-called experience.

The role of voltage transformer and current transformer

 AC induction cooling fan motor
Specifications
1.Customised
2. good quality
3. 20 years manufacturing experience

The high voltage proportional relationship to transform the 100 v or lower level standard secondary voltage, for the use of protection, measurement and instrumentation. At the same time, the use of voltage transformer can be high voltage and electrical isolation. Although also be in accordance with the working principle of 3 phase induction motor electromagnetic induction voltage transformer equipment, but its electromagnetic structure compared with the current transformer is just the opposite. Voltage transformer secondary circuit is high impedance circuit, the size of the secondary current is decided by the impedance of the loop. Secondary load impedance, small secondary current increase, makes a in a component of current automatically to meet electromagnetic balance of the relationship between the primary and secondary side. A voltage transformer is, as it generator set spare parts were, structure and using a limited form of special transformer. Electromagnetic current transformer is widely used in power system (hereinafter referred to as "current transformer"), its working principle is similar to the transformer.

 Y series best cast iron three phase induction motor
Specifications
1. 20 years manufacturing experience
2. 12 months guarantee
3. low noise and temperature rise
4. high starting torque

The principle of current transformer wiring, as shown on the left. The characteristics of the current transformer is: (1) a coil in series in the circuit, and as a result, the number of turns in a coil current depends on the load current of the circuit under test. And has nothing to do with the secondary current; (2) current transformer secondary coil of the current meter and relay to the coil impedance is very small, so under normal circumstances, current transformer run in to a short-circuit condition. The ac motor ratio of the current transformer primary and secondary rated current, called the rated mutual inductance of the current transformer ratio: kn = I1n/I2n Because of one coil rated current I1n standardization, secondary coil rated current I2n unification of 5 (1 or 0.5), so the rated mutual inductance current transformer ratio have also been standardized. Kn can be approximately expressed as transformer primary and secondary winding turn ratio, namely the kn material kn = N1 N2 / type www.dongfeng- motor.com of N1, N2, for one, two coil number of turns.

The analysis of the causes of leakage of transformer oil - seal structure

I plant oil leakage current transformer are mainly concentrated in four period of current transformer installed in the switching station,four period of current transformer is hunan liling cichang the mid - 90 - products,has been running more than eight years.Current transformer porcelain jacket with expander and motor magnet tank adopts hanging flange connection,this structure has to be eliminated,manufacturers are now used for pressure coil flange connection,compared with the hanging type connection,pressure coil flange connection has the advantage that can make the flange surface stress more evenly.

Manufacturers motor run capacitor of technical improvement,also can prove the existence of hanging join some shortcomings. Current transformer primary winding through the upper porcelain set of four terminals,derivation from the scene of the collapse of the transformer terminals can be found electricalmotor1.blogspot.com at a time,a terminal nanjing cichang the production of transformer and porcelain set of seal,the internal and external two flat pad.And a terminal liling,cichang production of transformer seal only outside a plane pad.Sealing structure differences make liling,cichang transformer produced a joint terminal sealing surface oil leakage occurred frequently.But now the liling manufacturer has also made the improvement to this sealing structure,in electrical motor a terminal seal face to add a seam allowance,o-rings seals,how to be in one step.

Permanent magnet synchronous motor in the elevator of the security and reliability of the development and application

Permanent magnet synchronous motor in elevator design,production,development and utilization,are increased highland elevator traction system security and reliability.When traction and braking failure or other failure cause the elevator upward slide line direction,and speed,it has safety protection,meet the technical standards of GB7588-2003 (elevator manufacture and install security specification 9.10 capsules upgoing overspeed protection device requirements.The use of permanent magnet wholesalemotor.blogspot.com synchronous traction motor of elevator,lost in the TV and remove the dot will grow motor armature winding short section (or short after concatenated adjustable resistor),when a speeding (regardless of upward and downward) failure,speed control system detected signals,immediately cut off power supply circuit of controller,and the motor armature winding short answer (or short after series adjustable resistor).

At this point,the stillness of the winding cutting rotating magnetic fields produced by permanent magnet and the induction electromotive force,caused by the armature winding in closed loop current,the current in the magnetic field under the action of torque,attempt to drive the armature low speed permanent magnet generator winding with magnetic rotation; at the same time,the torque is the moment of the effect on the rotor magnetic pole,trying to make the rotor end with the armature winding of the stator,is a braking torque.The process is similar to dc motor braking energy,against falling so as to realize the speed (brake torque can be adjusted through the resistor the slide speed controllable).

Interaction between permanent magnet and closure of the armature winding,this generates parking autistic non-contact two-way protection,greatly increase the safety and reliability of the elevator,especially reduced all kinds of high-speed elevator safety clamp cheese block caused by high temperature damage in high speed motion security risks.generator stator Because the gearless traction machine of coaxial traction wheel and motor,traction wheel and brake wheel parts,usually as a result,by

adopting the technology of gearless permanent magnet synchronous motor,don't set up overspeed

protection system,in the elevator in the acceptance inspection,of course,also can make the request.In

addition,the synchronous motor can be done by the armature winding for dc load zero speed parking,in order to be truly need not brake of mechanical braking,parking realizes the electrical zero speed.Can help to prevent slide due to brake failure of failure,to three phase induction motor further improve the reliability of the system.

Three-phase asynchronous motor connector

A change, triangular connection motor y connection Normal operation by delta connection of three-phase asynchronous motor, in order to reduce power use, can take three phase electric fan motor parts windings into star after online on the power supply voltage of 380 v, about 34% of the rated power is the power of the motor. For example, the 380 v delta connection 10 KW three-phase asynchronous motor to change into a star, meet online voltage of 380 v three-phase power use, at this time the power output of the motor is about 3.4 KW. Second, the three-phase asynchronous motor single-phase asynchronous motor Y connection and delta connection of three-phase motor changes the same way. Open the three-phase asynchronous motor terminal box, between any two phase power terminal access to a capacitor. The capacitor between V1 and W1, for example, it is at this point to connect single-phase power supply between the U1 and V1 or W1 (assuming the power of connect between the U1 and V1 motor, the power supply in U1 and electric opportunity inversion between W1,) can transform the original three-phase asynchronous motor converted a single-phase asynchronous motor. This method is especially suitable for no occasion of three-phase power supply using three-phase asynchronous motor. The capacity of the capacitor C = KP obtained are available, and where C is the capacity of the capacitor, the unit is the micro method (u F); P is the power of the motor, the unit is a kilowatt (KW); K is the empirical coefficient, take 0.06 when y-connection three-phase asynchronous motor, triangle sexual connection for 0.1. For example, 10 kw three-phase asynchronous motor when the star connection KP = C = 0.06 x 10 = 0.6 u F; 10 kw three-phase asynchronous motor triangle connection KP = C = 0.1 x 10 u F = 1. Changed to: after instead www.dongfeng-motor.com of capacitor terminals, such as the case of U1 power cord, another power cord by V1 connector on the W1 can realize inversion, the inversion of the inversion principle of single-phase asynchronous motor with the same principle Connect power: after the change is a single-phase capacitance motor, its effective power is 70% of the original motor power, for example: 10 kw three-phase asynchronous motor connector into effective power single-phase capacitor motor is about 7 kw. Convert into single-phase capacitor start motor, its effective power is 40% of the original asynchronous motor motor power, for example: 10 kw three-phase asynchronous motor connector into effective power for 4 kw single-phase capacitor start motor. To pick up after each phase winding voltage for no more than the rated voltage of the winding. What kind of motor depends on specific convert into being dragged the power of agricultural machinery. When convert into single-phase capacitor start motor, need to add one more time relay, wiring method is: put the time delay of time relay to disconnect the instantaneous closure in series capacitor circuit, the normally closed contact of time relay coil in parallel on both ends of single-phase power supply (time relay coil of the rated voltage is the same as the power supply voltage). After connected circuit, adjust the delay time of time relay, can work normally. Its working principle is: when switched on, time relay and motor for electricity at the same time, the capacitor circuit switched on, the motor starts, when the speed reached about 80% of the rated speed (implementation) by adjusting the delay time relay time delay disconnect instantaneous closure of time relay normally closed contacts disconnect, cut off the capacitor circuit, motor function.