1. What happens if I connect a capacitor to a generator load?
: Interfacing a capacitor across a generator generally further develops power factor, however it willhelp depends up on the motor limit of the alternator, any other way the alternator will be finishedstacked because of the additional watts consumed because of the enhancement for pf. Furthermore, don't associatea capacitor across an alternator while it is getting or with next to no other burden.
2. Why the capacitors works on ac only?
: By and large capacitor gives limitless protection from dc parts (i.e., block the DCparts). It permits the air conditioner parts to go through.
3. Explain the working principal of the circuit breaker?
Electrical switch is one which represents the deciding moment the circuit. It has two contacts specifically fixedcontact and moving contact. Under ordinary condition the moving contact interacts withfixed contact consequently shaping the shut contact for the progression of current. During unusual andflawed conditions (when current surpasses the appraised esteem) a circular segment is delivered between the fixed andmoving contacts and subsequently it shapes the open circuit, Arc is smothered by the Arc Quenchingmedia like air, oil, vacuum and so forth
4 How many types of colling system it transformers
1. ONAN (oil natural, air natural)
2. ONAF (oil natural, air forced)
3. OFAF (oil forced, air forced)
4. ODWF (oil direct, water forced)
5. OFAN (oil forced, air forced)
5. What is the function of anti-pumping in circuit breaker?
whenever breaker is shut down at one time by close press button, the counter siphoning contactor
forestall re close the breaker by close press button later on the off chance that it currently close.
6. What is stepper motor? What is its uses?
Stepper motor is the electrical machine which act upon input pulse applied to it.it is one type of synchronous motor which runs in steps in either direction instead of running in complete cycle.so, in automation parts it is used.
7 Tell me in detail about c.t. and p.t.?
The term C.T implies current transformer, and the term P.T implies likely transformer.In circuit where estimations of high voltage and high current is involved, they are utilized there. Especially while an estimating gadget like voltmeter or ammeter can't gauge such highworth of amount on account of huge worth of force because of such high worth it can harm theestimating device.so, CT and PT are presented in the circuits. They work on a similar guidelineof transformer, which depends on linkage of electromagnetic transition created by essential withoptional. They work on the proportion to they are planned. For example assuming CT is of proportion 5000\5A and it hasto quantify optional current of 8000A.then ANS=8000*5\5000=8Aand this outcome will begiven to ammeter .and subsequent to estimating 8A we can work out the essential current. Same is theactivity of PT yet estimating voltage
8. There are a Transformer and an induction machine. Those two have the same supply. For which device the load current will be maximum? And why?
The engine has max load current contrast with that of transformer in light of the fact that the engineconsumes genuine power and the transformer is just delivering the functioning motion and it's notconsuming. Subsequently the heap current in the transformer is a result of center misfortune so it is least
9. What is power factor? Whether it should be high or low? Why?
Reply: Power variable ought to be high to get smooth activity of the framework.Low power factor implies misfortunes will be more.it is the proportion of genuine influence to evidentpower. It must be in a perfect world 1. In the event that it is too low, link over warming &equipmentover-burdening will happen. On the off chance that it is more prominent than 1, burden will go about as capacitor and startstaking care of the source and will cause stumbling. (Assuming that pf is unfortunate ex: 0.17 to meet real powerload needs to draw more current (V consistent), bring about more misfortunes in the event that pf is great ex: 0.95 tomeet genuine power load needs to draw less current (V steady), bring about less misfortunes)
10 What is SF6 Circuit Breaker?
SF6 is Sulfur hexa Fluoride gas. Assuming that this gas is utilized as bend extinguishing medium in a Circuitbreaker implies SF6 CB
11 What is meant by insulation voltage in cables? Explain it?
It is the property of a cable by virtue of it can withstand the applied voltage without rupturing it is known as insulation level of the cable
12 Why we do 2 types of earthing on transformer (i.e. :) body earthing & neutral earthing, what is function. i am going to install a 5oo kva transformer & 380 kva DG set what should the earthing value?
The two types of earthing are Familiar as Equipment earthing and system earthing. In Equipment earthing: body (non-conducting part) of the equipment should be earthed to safeguard the human beings. System Earthing: In this neutral of the supply source (Transformer or Generator) should be grounded. With this, in case of unbalanced loading neutral will not be shifted.so that unbalanced voltages will not arise. We can protect the equipment also. With size of the equipment (transformer or alternator) and selection of relying system earthing will be further classified into directly earthed, Impedance earthing, resistive (NGRs) earthing.
13 What is the difference between MCB & MCCB, Where it can be used?
MCB is smaller than normal electrical switch which is warm worked and use for shortcircuit insurance in little current rating circuit. MCCB shaped case electrical switch and iswarm worked for over load current and attractive activity for moment trip in impede. Under voltage and under recurrence might be inbuilt. Ordinarily it is utilizedwhere typical current is more than 100A
14 . What are the transformer losses?
TRANSFORMER LOSSES - Transformer misfortunes have two sources-copper misfortune and attractivemisfortune. Copper misfortunes are brought about by the obstruction of the wire (I2R).Magnetic misfortunes are brought about byprofoundly. Copper misfortune is a consistent after the curl has been woundwhat's more, accordingly a quantifiable misfortune. Hysteresis is misfortune is consistent for a specific voltage and current.Vortex current misfortune, in any case, is different for every recurrence gone through the transformer.
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