Electrical Engineering

According to lenz law , "effect opposes the cause "

now due to flux cutting action emf induce in coil opposes the flux by which this emf is induced . So this opposition by induced current of staring current is called inductance .

24VACRMS * 1.414 = 33.94VACPEAK

The unloaded filtered DC voltage is 33.94V

The unloaded unfiltered voltage will be a single polllarity AC voltage with a peak of 33.94V

Maximum power transfer happens in a circuit when the resistance of the circuit equals the reactance.

Impedance Z = R + jX. At R=X, maximum power transfer happens.

repetition rate of signal

A symmetrical fault is a fault where all three phases are experiencing the same thing. This is also called a three phase fault, since all three phases are involved.

altinator

OCTC means off circuit tap changer (off load tap changer) and OLTC means on load tap changer. in octc we can change the tap position while the transformer is in off condition only. we can not change the tap position of octc in charged condtion of the transformer. the tap position of octc can be change in deenrgise condion of transformer only means if you nwant to chang the tap position firstly you will have to deenrgise the power transformer then you can change the tap position of octc.while in oltc we can change the tap position of OLTC in charged condition of power transformer. This is the basic diffirence between OCTC and OLTC.generally the OCTC used in single phase generating transformer (G.T.Power Transformer) and OLTC used in three phase powwer transformers like standby transformer and auto transformer in power plants and switch yards. for any other question please mail me at (ashu_uit2007@yahoo.co.in )

This is the rated output of the transformer, obtained by multiplying the rated secondary voltage by the rated secondary current. And it's 'kV.A', not 'kva'.

no

An 'oscillating' neutral can exist when the star point of a three-phase, star (wye) connected, secondary winding becomes disconnected from earth (ground) -e.g. if copper thieves have removed the earth conductor or it simply becomes disconnected. This results in a 'floating neutral', in which the phase voltages are no longer necessarily equal to each other (in other words, the three phase voltages have become 'unbalanced') the extent to which depends upon how unbalanced the supplied load is. An 'oscillating' neutral occurs when the displacement of the neutral point changes as it responds to changes in the unbalanced load currents.

Mutual inductance describes the process by which a changing current in one coil, creates a changing magnetic flux which, when it links with a second coil, induces a changing voltage into that coil.

It is usually 240. Two lines enter your house, carrying 120 volts each, but they are out of phase by 180 degrees, so the two combined entering your house provide 240 volts, which is necessary for powering central air conditioning systems. You also have the option of powering everything else in your house with 120 volts because of the phase difference of 180 degrees without the need of a 2:1 turns ratio transformer in your house. You breaker box in you basement is wired to take advantage of this phase difference, supplying the 240 and 120 volt sources to the places that they are needed. This is a huge advantage of AC power.

'Loading effect' applies to voltmeters, or to multimeters when set to measure voltage. It describes the change in a circuit's resistance when the resistance of the voltmeter is taken into account. It's effect is to cause the resulting measuredvoltage to be different from the actual voltage which would appear without the voltmeter connected. The loading effect is minimised by ensuring that the internal resistance of the voltmeter is significantly higher than the resistance of that part of the circuit to which it is connected. For general voltage measurement, this is usually the case anyway, but when measuring circuits which, themselves, have very high resistance care must be taken over the choice of voltmeter to be used.

Because many electronics, like power supplies, have internal energy storage in the form of capacitors. If you were to short the terminals, you would be shorting out the internal capacitors and thus creating a potentially hazardous situation. "Completing the circuit by internal resistance" allows the energy stored in the internal capacitors to bleed off slowly because the internal resistance is larger than a short.

no load means the motor is acting like a coil

A transformer is fundamentally a set of coils; therefore, a transformer is an inductive load. However, by "transformer load", you seem to mean "the load that is connected to a transformer". Whether that load is inductive or capacitive depends mostly on what is hooked up to the transformer.

Divide VA rating with the Voltage and get Amp rating.

So say you have a transformer that delivers 26V, 80VA, that means a maximum current of 80/26=3.07A for a resistive load.

Rather than where? Circuit breakers are always located in substations.

Many high-voltage overhead line faults are temporary in nature -e.g. a branch hitting a line conductor during a storm. An 'autorecloser' mechanism is designed to automatically reclose a circuit breaker after it has tripped. If the fault has cleared itself, then the circuit breaker will remain closed; if not, the autorecloser mechanism can be set to reclose the circuit breaker several times (typically 3) before, finally, locking the circuit breaker open. Autoreclosers are often used in conjuction with 'sectionalisers'; these are non-load breaking switches which will disconnect sections of line towards the end of a feeder, in the hope that any fault has existed beyond that point and will be cleared before the autorecloser recloses the circuit breaker.

The internal gain of an amplifier is the gain or the amplification factor of the transistor used in it....................it is internal because it is fixed for transistors while manufacturing..................

This isn't necessarily the case. Tap changers are normally located on the high-voltage side of the transformer, regardless of whether it is a step up or a step down type. This is because the current is lower on the h.v. side, enabling smaller contacts, etc., to be utilised.

No

There is no 'equivalent resistance' for three resistors connected in star.