Electrical Engineering

Electricity is the interaction of many components. These include electric charges, electric fields, electric potentials, electric currents, and electromagnets.

Use a multimeter on the ohms scale. put the two leads on each of the primary terminals and read the resistance. Then put the leads on the secondary side of the transformer and read the resistance.

Unit or say Rating of transformer is in KVA and not in KW because copper loss of a transformer depends on current and iron loss on voltage. Hence, Total transformer loss depends on volt-ampere ( VA ) and not on phase angle between voltage and current i.e. it is independent of load power factor. That is why Unit or say Rating Of Transformer Is In KVA and not in KW.

load test on dc shunt generator is a test to plot the internal and external characteristics of the generator.

4 pole, 5 wire

A 120V power supply connected to a 30 Ohm resistor will produce 120/30 or 4 amps of current.

Connect ammeter in series and voltmeter in parallel to the circuit

A fuse box is a box that holds fuses that once blown, they have to be replaced. A circuit breaker will reset itself after it has cooled down. +++ NO: that is a thermal-overload protector.

A circuit breaker is not normally auto-reclosing (except for certain types in power-stations). It has to be re-set manually, so fails safely: it stays off until you have traced and corrected the fault,or disconnected the guilty appliance, that caused it to release.

A fuse is just a thin wire filament that melts (fuses) if the current drawn exceeds its limit.

Ohm's Law: Current = Voltage divided by resistance

9 volts divided by 3 ohms = 3 amperes.

A thevenin's equivalent circuit uses a voltage source and the norton's equivalent circuit uses a current source.

Thévenin's theorem for linear electrical networks states that any combination of voltage sources, current sources and resistors with two terminals is electrically equivalent to a single voltage source V and a single series resistor R. For single frequency AC systems the theorem can also be applied to general impedances, not just resistors. The theorem was first discovered by German scientist Hermann von Helmholtz in 1853, but was then rediscovered in 1883 by French telegraph engineer Léon Charles Thévenin (1857-1926).

Norton's theorem for electrical networks states that any collection of voltage sources and resistors with two terminals is electrically equivalent to an ideal current source, I, in parallel with a single resistor, R. For single-frequency AC systems the theorem can also be applied to general impedances, not just resistors. The Norton equivalent is used to represent any network of linear sources and impedances, at a given frequency. The circuit consists of an ideal current source in parallel with an ideal impedance (or resistor for non-reactive circuits).

Norton's theorem is an extension of Thévenin's theorem and was introduced in 1926 separately by two people: Hause-Siemens researcher Hans Ferdinand Mayer (1895-1980) and Bell Labs engineer Edward Lawry Norton (1898-1983). Mayer was the only one of the two who actually published on this topic, but Norton made known his finding through an internal technical report at Bell Labs.

If we apply Ohm's law, which is E = I x R and we have a voltage (E) of 110 volts and a current (I) of 10 amps, we can use the variation of the formula to solve. That variation is R = E / I and the resistance (R) is discovered by dividing the voltage by the current. R = E / I = 110 / 10 = 11 ohms

Here is the list of actual exam or homework questions the Asker wishes to have someone write the answers for him to copy without looking them up for himself:

: 1) What is a slit ring and a slip ring in electrical ... (machines?)

: 2) mention the application of the method of connection in brief : 3) what is the phase type (1phase, 3phase) and explain why not using 2phase : 4) what is cogging and hunting? explain briefly : 5) what is the difference between neutral and earth? explain briefly

acsr means all alluminum steel reinforced , it means it has a steel conductor inside for reinforcing just as animals has backbone , so names of the animals & birds names with backbone are used for ASCR.

AAC, All alluminum cable , the names of insects used

The primary winding is the winding connected to the supply, while the secondary winding is the winding connected to the load. The terms, 'primary' and 'secondary' are unrelated to voltage levels.

when transmission we usually use high voltages becoz at higher voltages current is less(p=vi,voltage is inversly proportional to current at constant power) so that we can minimize copper losses i2R losses.

The 'stator' is the generic term for the stationary parts of a machine, including its frame, magnetic circuit, poles, windings, etc.

You reduce ripple voltage by adding a low-pass filter. In the simplest case, you put a capacitor after the rectifier. The peak voltage will be the rectifier output voltage less the forward bias of the rectifier, while the minimum voltage will depend on current and capacitance. In a more complex case, you could use an LC filter, making the peak voltage smaller. Specifics are dependent on the power and performance requirements.

Loads or power-consuming devices are usually wired

A transformer is used to step up (increase) or step down (decrease) an alternating voltage with very little loss of energy.

They pass AC and block DC. So they are used in filters of various types as well as signal coupling. The capacitor is use to store the electric energy in the automobile ignition system. The capacitor is attached to the secondary winding of ignition coil. When contact breaker breaks the contact to the primary winding and sudden collapse of magnetic flux induces the high voltage to the secondary winding. This excess voltage is stored in capacitor. Capacitor releases the electric energy when it need. It protects cam and contact breaker points from corrosion or rusting.

Increase the voltage in the lines.

The stator is the stationary part of an electric generator or electric motor. The non-stationary part on an electric motor is the rotor. Depending on the configuration of a spinning electromotive device the stator may act as the field magnet, interacting with the armature to create motion, or it may act as the armature, receiving its influence from moving field coils on the rotor. The first DC generators (known as dynamos) and DC motors put the field coils on the stator, and the power generation or motive reaction coils on the rotor. This was necessary because a continuously moving power switch known as the commutator is needed to keep the field correctly aligned across the spinning rotor. The commutator must become larger and more robust as the current increases. The stator of these devices may be either a permanent magnet or an electromagnet. Where the stator is an electromagnet, the coil which energizes it is known as the field coil or field winding. An AC alternator is able to produce power across multiple high-current power generation coils connected in parallel, eliminating the need for the commutator. Placing the field coils on the rotor allows for an inexpensive slip ring mechanism to transfer high-voltage, low current power to the rotating field coil. It consists of a steel frame enclosing a hollow cylindrical core (made up of laminations of silicon steel). The laminations are to reduce hysteresis and eddy current losses.