Q3) A 220 V d.c series motor has armature and field resistancesof 0.15 Q and 0.10 Q respectively. It takes a current of 30 Afrom the supply while running at 1000 rpm. If an externalresistance of 1 Q is inserted in series with the motor,calculate the new steady state armature current and thespeed. Assume the load torque remains constant.

Answered: Image /qna-images/answer/1318bf61-d6e5-4084-bb0b-e4287d77c9fc.jpg

A 220 V d.c series motor has armature and field resistances of 0.15 Q and 0.10 Q respectively. It takes a current of 30 A from the supply while running at 1000 rpm. If an external resistance of 1 N is inserted in series with the motor, calculate the new steady state armature current and the speed. Assume the load torque remains constant.

A 220 V d.c series motor has armature and field resistances of 0.15 Q and 0.10 Q respectively. It takes a current of 30 A from the supply while running at 1000 rpm. If an external resistance of 1 N is inserted in series with the motor, calculate the new steady state armature current and the speed. Assume the load torque remains constant.

Understanding Motor Controls

4th Edition

ISBN:9781337798686

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter29: Single-phase Motors

Section: Chapter Questions

Problem 5RQ

See similar textbooks

Similar questions

In a no-load motor, a constant electromagnetic torque of 5 Nm is generated at t = 0. The engine reached 1800 revs in 4 seconds. Calculate motor inertia ignoring friction.
A. Incident sound waves in a dynamic pickup or microphone lead to the passage of AF current in the coil because- 1) The coil's motion within a magnetic field. 2) The motion within an electrostatic field.3) A DC voltage is applied to the coil. 4) Changes in the capacitive reactance across the coil. B. An intermittent (as opposed to continuous) motor is one in which the shaft revolves in- 1) An incremental motor. 2) A stepper motor. 3) A selsyn. 4) A fractional motor.
Find the horsepower rating of a motor running at 1,500 rpm and developing a torque of 105 lb–ft. (a). 22 (b). 28 (c). 30 (d). 36
A balanced star-connected load of (8 + j6) Q per phase is connected to a Balanced 3- phase 400-V supply. Find the line current, power factor, power
With a driveshaft turning at 2000 rpm , I then have a spring that can rotate a shaft 5000 rpm, I want this spring to assist in the drive of the driveshaft, how can I express that or calculate the effect of adding the spring would make. Including a spring system alongside a driveshaft that can assist the drive up to 5000rpm, how can I integrate the spring system to assist in the driveshaft drive, calculations on the change in rotation the spring would have of the driveshaft speed
A 7460 W split-phase motor running at 1750 rpm is used to drive a rotary pump. The pump should run continuously at approximately 1175 rpm. The center distance should not exceed 1118 mm. Space limits the diameter of the driven pulley to 292 mm. Determine: a. the pulley diameters, b. the belt size, and c. the number of belt required.
For a hydrulic motor , define volumetric, mechanical, and overall effiency.
A motor, operating clockwise is coupled through a belt drive to rotate an industrial exhaust fan at 500 rpm. The diameter of the motor sheave is 4 in. and the sheave on the fan is 14 in. Determine the belt speed.
Calculate the power "P" in watts of a motor rotating at a speed "n" of 1740 r/min and producing a torque "t" of 1.4 N·m (12.4 lbf·in).
a- What are the assumption rigid rotor model is based on? b-What are the limitations of this model?
An 8 pole, lap connected armature has 500 conductors and its generated e.m.f is 120V. If the flux per pole is 20 mWb, then the speed of machine is,
What is the purpose of the Tip Mass in the model of the Magnetostrictive vibration energy harvester?