Find the initial and final values of the armature current, Electrical Engineering

Assignment Help:

Q. A 7.5-hp, 250-V, 1800-r/min shuntmotor, having a full-load line current of 26 A, is started with a four-point starter. The resistance of the armature circuit, including the interpole winding, is 0.48 ; and the resistance of the shunt-field circuit, including the field rheostat, is 350 . The resistances of the steps in the starting resistor are 2.24, 1.47, 0.95, 0.62, 0.40, and 0.26 , in the order in which they are successively cut out.When the armature current is dropped to its rated value, the starting box is switched to the next point, thus eliminating a step in the starting resistance.

Neglecting field-current changes, armature reaction, and armature inductance, find the initial and final values of the armature current and speed corresponding to each step.


Related Discussions:- Find the initial and final values of the armature current

Dc machiunes, 1,Operation of face plate starter 2;Operation of a shaded pol...

1,Operation of face plate starter 2;Operation of a shaded pole motor 3,3 explained demerits of a rheostat method of starting adc machines

Calculate the reflection of wedge, The corners of wedge-shaped block are A(...

The corners of wedge-shaped block are A(0,0,2), B(0,0,3), C(0,2,3), D(0,2,2), E(-1,2,2) and F(-1,2,3) and the reflection plane goes the Y-axis at 450 between (-X) & (Z) axis. Calcu

Electrical distribution system, 1. Name the three parts of a programmable l...

1. Name the three parts of a programmable logic controller (PLC) and explain why the PLC is preferred by designers over electromechanical relays. 2. Medium-voltage circuit break

Illustrate the satellites in outer space, Illustrate the satellites in oute...

Illustrate the satellites in outer space Satellites in outer space transmit signals to Earth. Computers in vehicles (for example car, airplane or ship) receive and interpret th

Pu value, the p.u. reactance of a 25 MVA, 13.2 kV alternator 0.5 p.u. On a ...

the p.u. reactance of a 25 MVA, 13.2 kV alternator 0.5 p.u. On a base of 50 MVA and 13.8 KV the p.u. value shall be

Program counter , Program Counter (PC) It is a   16 bit  register.  It ...

Program Counter (PC) It is a   16 bit  register.  It is a memory  pointer. It stores  the memory address  of the next  byte of the program to be executed. Memory  address is of

Find the minimum sum of products, Given that , f(a,b,c,d,e) = Σm (6,7,9,11,...

Given that , f(a,b,c,d,e) = Σm (6,7,9,11,12,13,16,17,18,20,21,23,25,28) using a Karnaugh map. (i) Find the essential prime implicants (ii) Find the minimum sum of product

Single-axis autopilot control system of an aircraft, Q. Single-axis autopil...

Q. Single-axis autopilot control system of an aircraft? Figure (a) shows the block diagram of a simplified single-axis (pitch, yaw, or roll) autopilot control systemwith digita

Diffusion current, Diffusion Current : The carrier currents are also ...

Diffusion Current : The carrier currents are also due to concentration gradients in the doped material which lead to diffusion of carriers from high concentration region to l

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd