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 armature winding has 51 slots, each slot containing 20 conductors. What will be the voltage generated in … [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 conditions2. How does a Circuit Breaker different from Switch?Switch is just a device when can be able to open and close the circuit during normal operation. Whereas on the other hand circuit … [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 Factor In the case of the transformer and generator, the designer or manufacturer does not know … [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? The dc supply can not be used for the transformers. The transformer does not work on DC supply. The reason is explained below. Why Transformers are rated in KVA and not in KW? Working Principle of Tranformer The transformer works on the principle of mutual induction, for which current … [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 line. 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 through a body. So for the bird to be shocked there would need to be a current running through her body. … [Read more...] about Why Birds don’t get Electrocuted on Touching Power Lines?