Electrical World

Hello Engineers. Today we are sharing alternator interview questions with answer. Q. 1. What are the two types of turbo-alternators ? Ans.  Vertical and horizontal. Q. 2. How do you compare the two ? Ans. Vertical type requires less floor space and while step bearing is necessary to carry the weight of the moving element, there is very little friction in the main bearings. The horizontal type requires no step bearing, but occupies more space. Q. 3. What is step bearing ? Ans. It consists of two cylindrical cast iron plates which bear upon each other and have a central recess between them. Suitable oil is pumped into this recess under considerable pressure. Q. 4. What is direct-connected alternator ? Ans. One in which the alternator and engine are directly connected. In other words, there is no intermediate gearing such as belt, chain etc. between the driving engine and alternator. Q. 5. What is the difference between direct-connected and direct-coupled units ? Ans. In

Q.1 A generating voltmeter is used to measure A. Impulse voltage B. AC voltage C. dc voltage D. All Answer : c Q.2 A series capacitance voltmeter can measure A. DC voltage B. Rms value voltage C. Ac voltage D. All Answer : c Must Read: Transformer Interview Questions Q.3 cvt when tunned does not have A. Ratio error B. Phase angle error C. Both a and b D. None Answer : b Q.4 Electrostatic voltmeter can measure A. Dc voltmeter B. Ac voltmeter C. Both a and b D. None Answer c Q.5 sphere gaps are used to measure A. Dc voltage B. Ac voltage C. Impulse voltage D. All Answer d Q.6 hall generators are normally used to measure A. Impulse voltage B. Unidirectional impulse current C. Any type of impulse voltage D. All Answer b Q.7 for measuring high impulse currents, the best type of shunt is A. Squirrel cage B. Bifilar strip C. Disc D. Coaxial tubular Answer d Don't Miss : Alternator Interview Questions Q.8 to measure a high voltage of peak

1. Electrical conduction in gases was first studied in A. Loeb B. Maxwell C. Townsend D. None Answer : c Q.2 SF6 is a A. Natural gas B. Electronegative gas C. Ionize gas D. Non attaching gas Ans : b Must Read: Electrical Engineering Interview Questions Q.3 Minimum sparking potential of air is A. 40 v B. 100 v C. 4.4v D. 325v Answer : d Q.4 The requirement of gases for insulation purpose is A. High dielectric strength and thermal stability B. High thermal stability C. High dielectric strength only D. None Answer : A Q.5 Transformer oil is A. Askeral B. Silicone oil C. Polyster oil D. Mineral oil Answer: D Q.6 The breakdown strength of mineral oil is about A. 20kv/mm B. 30-40 kv/mm C. 50 kv/mm D. None Answer : B Q.7 Dielectric constant of mineral oil is A. 1.5 to 2.0 B. 2.2 to 2.4 C. 3.0 to 3.5 D. None Answer : b Q.8 maximum dielectric strength obtained with pureliquid A. 100 kv/mm B. 10 kv/mm C. 1mv/mm D. All Answer :a Q.9 which

The electronic doorbell in this article is the most simplest among the advance projects in this website. There are many other benefits of the project doorbell. The circuit for the electronic doorbell here will help realise whether the visitor is in front door or in back door. More about there is two LED indicatorwith different colours which provide visual indication to check if anyone had come nor not in your absence. PART LIST Transistors T1,T2,T5 BC148B T3,T4 BC158B T6 AC128 Diodes D1,D2,D3,D4 1N4001 D5 GREEN LED D6 RED LED Capacitors C1,C2,C3 0.01 μF Resistors R1,R7,R8.R9,R10 2.2 KΩ R2 47Ω R3,R4 100KΩ R5,R6 10KΩ R11,R12 330Ω Miscellaneous S1 ON/OFF toggle switch for memory S2,S3 Switch for doorbell BATT 9-Volt Battery LS Loud Speaker 8Ω OTHERS  PCB , Connecting Wires, Hardware,enclosure etc Circuit Description Working Principal The presented circui