Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
In this case, the armature is connected in series with the field coils. Thus Ia = If = I
NB. At starting, the back emf is zero (because the motor is initially stationary) and hence the current is very large (limited only by the field and armature resistances). Hence the starting torque will be extremely large and if no load is applied (so that the torque requirement is small) the motor will accelerate rapidly to dangerously high speeds. A series connected motor must be started with a mechanical load attached to prevent the speed at start up rising to damaging speeds.Note that saturation of the magnetic material in the motor can occur at high currents and then the flux generated by the field coils becomes independent of current. This causes the characteristics to become similar to that of a shunt wound motor that also has an approximately constant field flux.
The series motor gives a high starting torque (proportional to 1/I2 ), 2.5 to 3 times the full load (rated) torque) but it falls rapidly as the speed increases. Applications: heavy duty, with intermittent starting under conditions where a mechanical load is always present - e.g. traction, cranes, hoists. etc
The speed of a series wound motor may be controlled by the addition of a resistor in parallel with the field coil. This divertssome of the current away from the field coil, reducing the field strength and hence the back emf at a given speed. The additional resistor is called a 'diverter'. The speed must increase to compensate this reduction in back emf. . Hence a reduction in the diverter resistance reduces the field strength and increases the speed of the motor.
equilizing connection
Explain LDA, STA and DAA instructions LDA copies the data byte into accumulator from the memory location particular by the 16-bit address. STA copies the data byte from the acc
Q. Sketch a typical circuit for a 2-input, 4-output decoder.
how can i calculate that is following signal is periodic or not? X[n]= ?_(k=-8)^8¦?{d[n-4k]-d[n-1]-4k]}?
SOD Output Serial output data single bit can be sent out through this pin using SIM command discussed in details in chapter8.
Program Analysis We have to find the greater of two given number. We can store the given numbers in two different registers ( suppose register A and B). Then we will com
advantages and disadvantages of direct and r c coupling
hi there i just need help for Electrical Engineering Design Report about any topic (prefer charger and inverter) which should be include Summary,Table of contents,Introduction,Body
Q. What is error-rate control? A system is said to possess error-rate damping when the generation of the output in some way depends upon the rate of change of the actuating sig
In real life, transformers have losses which cause their behaviour to deviate from the ideal. Explain the reasons for this non-ideal behaviour
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd