Why Induction Motor Takes High Starting Current?
Working Principle of Induction Motor: The induction motor draws a high starting current compared to the running condition. The starting current of the induction motor … Read more
Electrical
Polarization Index Test and DAR Test
The polarization index test is a 10-minute to 1-minute ratio test of insulation resistance. Similarly, the DAR test is a 60-second to 30-second insulation resistance … Read more
What is the effect of the speed regulator of a ceiling fan on power consumption?
This article describes how the power consumption of a ceiling fan changes with a change in the speed through a fan regulator. The conventional fan … Read more
How to Calculate Burden of CT
The burden of the current transformer is expressed in VA. The total VA burden should be considered when CT is used for measuring or protection … Read more
Back EMF and its Significance in DC Motor
The back EMF momentarily opposes the armature voltage when the speed of the DC motor is changed, and thus, it limits the armature current. What … Read more
Transformer Over Fluxing Protection
The transformer over-fluxing protection protects the core from overheating caused by over-fluxing. The voltage and frequency ratio(v/f) is responsible for over-fluxing in the transformer. In … Read more
Over Fluxing in Transformer
How does the transformer work? The transformer has two coils wound around a common magnetic core. When an alternating voltage is applied to the primary … Read more
Why DC Series Motor should not be Started at No Load
The DC series motor attains dangerously high speed when we run it on no load. The main reason for overspeeding is that at no load, … Read more
Why is Star Delta Starter Preferred with an Induction Motor?
In star delta starting, the phase voltage is 58 % of the line voltage when the motor is first connected in the star connection. The … Read more
DC Shunt Motor : Construction, Speed Control & Characteristics
In this post, we will discuss the construction, speed control, and characteristics of DC shunt motors. CONSTRUCTION OF SHUNT DC MOTOR The field winding of … Read more