1. A shunt generator delivers 450 A at 230 V and the resistance of the shunt field and armature are 50 Ω and 0.03 Ω respectively. Calculate the generated e.m.f? Solution: The Generator Circuit is as shown in the figure, 2. A four pole generator having wave-wound … [Read more...] about 5 DC Generator Problems with Solution – Part 1
1. What is a Circuit Breaker? Circuit Breaker is a mechanical device designed to close or open contact members, thus closing or opening an electrical circuit under the normal or abnormal conditions 2. How does a Circuit Breaker different from Switch? Switch is just a … [Read more...] about Circuit Breakers – Interview Questions with Answers
Unlike Generators and Transformers, Electric Motors are rated in kW instead of kVA. We have already discussed why electric transformers are rated in kVA. This article explains why electric motors are rated in kW. We know that, kVA = Voltage×Current kW = Voltage×Current×Power … [Read more...] about Why Electric Motors are Rated in kW and not in kVA?
Did you ever think about what will happen to a transformer on dc supply? In this article, you will learn why the transformer does not work on the DC supply. You already know that dc supply cannot be used for the transformers. The transformer does not work on the DC supply. The … [Read more...] about Why Transformer does not work on DC supply?
You may be amazed at why the birds don't get shocked when they sit on high voltage overhead power lines. People often ask why don't birds get electrocuted on power lines. The possible reasons are discussed in this article. An electric shock is caused by a flow of current … [Read more...] about Why Birds don’t get Electrocuted on Touching Power Lines?
Each year in France, for example, 200 people die of electrocution and 500 suffer serious injuries, often permanent burns, respiratory paralysis, cardiac arrest, etc. The various level electric current have different effects on the human body. Here we are discussing the … [Read more...] about Effect of Electric Current on Human Body at 50 Hz
The effects of voltage and frequency variation on the transformer is discussed in this article. Usually, power transformers are not subjected to wide frequency variations. Also, modest voltage variations occur on power transformers. But it is interesting to consider their … [Read more...] about Effects of Voltage and Frequency Variation on Transformers
Single-phase motors are the most familiar of all-electric motors because they are extensively used in home appliances, shops, offices etc. It is true that single-phase motors are a less efficient substitute for 3-phase motors but 3-phase power is normally not available except … [Read more...] about Single Phase Induction Motor – Working Principle and Construction