Question
Download Solution PDFWhy is a starter necessary to start a DC motor?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFStarters in DC motors
Starters are used to protect DC motors from damage that can be caused by very high inrush currents and torque during startup.
This is done by providing external resistance to the motor, which is connected in series to the motor’s armature winding and restricts the current to an acceptable level.
\(V=E_b+I_aR_a\)
where, V = Terminal voltage
Eb = Back EMF
Ia = Armature Current
Ra = Armature Resistance
As Eb is directly proportional to the speed. So, at the starting speed is zero, hence Eb = 0
At starting:
\(V=0+I_aR_a\)
\(I_a={V\over R_a}\)
Hence, starters are used to limit starting current as the current at the starting of the motor is high.
Last updated on Jul 18, 2025
-> MPPGCL Junior Engineer Notification 2025 has been released for various fields of post (Advt No. 3233).
-> MPPGCL has announced a total of 90 vacancies for Civil, Mechanical, Electrical, and Electronics Engineering (Junior Engineer).
-> Interested candidates can submit their online application form, from 23rd July to 21st August 2025.
-> MPPGCL Junior Engineer result PDF has been released at the offiical website.
-> The MPPGCL Junior Engineer Exam Date has been announced.
-> The MPPGCL Junior Engineer Notification was released for 284 vacancies.
-> The selection process includes a Computer Based Test and Document Verification.
-> Candidates can check the MPPGCL JE Previous Year Papers which helps to understand the difficulty level of the exam.