Electrical Engineering

Is either;

A. the length of the wire

B. the diameter of the wire

c. the location of the wire

D. the temperature of the wire

The number of current-carrying conductors allowed in a conduit before derating is specified by the National Electrical Code (NEC). Generally, if you have more than three conductors in a conduit, you need to start derating the ampacity of the conductors. Specifically, for more than three conductors, the ampacity of each conductor must be reduced based on the number of conductors present. For example, with 4 to 6 conductors, the ampacity is typically reduced to 80%, and with 7 to 9 conductors, it’s reduced to 70%.

A Linear power transformer coil? use an Ohm meter and check the resistance of the coils.

No resistance is an open circuit.

Also check for a cross circuit from one side of the transformer to the other.

All the bulbs will go out.

In a series circuit, the current at all points is the same. This is Kirchoff's Current Law. If you loosen or remove a bulb in a series circuit, the current at that bulb becomes zero, and by Kirchoff's Current Law, the current in every part of the circuit also becomes zero.

You measure current by inserting an amp meter in series with the circuit or using a clamp-on meter to measure current by induction. You measure voltage with a volt meter across the supply. You measure resistance in ohms across the resistance. Luckily all these functions are in the same meter in most cases.

To answer this question a voltage must be stated. W = A x V x pf.

The Chuo Shinkansen is a superconducting maglev line being built between Osaka and Tokyo Japan. Currently, a test facility in Yamanashi Japan is being upgraded to be a part of the final 272-mile corridor. The first phase of the train is expected to be open in 2027, and the full corridor by 2045.

Steel-reinforced aluminium cables are used for overhead lines because aluminium is much lighter than a copper conductor, despite not being quite as good a conductor as copper. The function of the steel reinforcement is to improve the tensile strength of the conductor.

No. Three phase service is something that you would need to request from your power company. You'd need to not only have service, you also need to have an electrician run 3 phase service into your home.

A volt meter is used to measure volts.

So what are volts???

Volts are what a volt meter measures.

Imagine water being pushed through a pipe. If the water in the pipe is falling from a container at a higher place, it goes through the pipe at a higher pressure... sort of like volts.

A larger pipe allows more water through, sort of like amps.

Any 2-year old can tell you that a train says "choo-choo". But trains have never actually made this sound.

A plethorea of sounds can be heard, just go trackside and listen, from the piercing note of a horn, to the roar of the diesel engine to the click-clack of the wheels on the joints in the rail to the squeal of steel wheel on steel rail, there are hundreds of sounds to enjoy.

Resistance of the circuit = (voltage across the circuit) divided by (current through the circuit)

The voltage between line and neutral is determined by the regulations in your country. This is specified as a nominal (named) voltage, together with its allowable variation expressed as a percentage of that nominal value. In the UK, for example, this is 230 V (+10%/-6%).

The start up current should be listed on the motor nameplate as FLA , full load amps.

A full wave rectifier chops the AC waveform so it can be converted into a clean DC signal. If you're looking at a spectrum analyzer of this output, it will look like 50 Hz, with a strong DC component, and multiple higher level harmonics of lesser value.

not you kan not start 22kw motor with 25kva generator (οχι)

In a 3 phase induction motor there is 6 wires frm the windings.Inwhich ,we can measure ohms value between each other.there are 2 different ohms value between each pair of three wires.

lets say,10 ohm and 30 ohm.low voltage and high voltage side.can anyone say is it right to find the wingings of star and delta side?

although the AC signal is rectified the output which we get is the pulsating DC which is not desired because many appliances wok on plain DC voltage . The pulsating DC can be viewed as AC + DC component of the signal

ripple factor of a rectified circuit is the ratio of AC component of signal to the DC component of the same rectified output signal. higher the ripple factor says that the signal is not smooth so lesser is its application.

the components used to smooth these type of signals or to remove the 'ripple voltage' as called filters

Zener diodes are mainly used as voltage sources.

Since they provide a reasonably constant voltage drop, even when current changes, they are useful in small power supplies as voltage regulators.

AC voltage, like the voltage in your house, is typically referred to as 120vAC. This means the voltage swings 120V positive and 120V negative 60 times per second (60 Hz) 360 degrees total (sine wave). Current and voltage go hand-n-hand so the current alternates with the voltage. the RMS value is what we experience at the output (160vAC is actually sent to the circuits)

Slip rings are needed to connect a rotating armature to external fixed circuits.

This might help you. First and foremost is the information the manufacturer puts on the nameplate of the motor. Second, the generic amperage can be found on motor charts that are on the Internet. Third you can use a formula to find the approximate amperage. HP = Amps x Volts x 1.73 x pf/746. Transposed for Amperage, Amps = HP x 746/Volts x 1.73 x pf. Use power factor = .9 For estimating a 10 HP motor running on 208 volts. Amps = 10 x 746/ 208 x 1.73 x .9 = 7460/323.85 = 23.03 amps. See how much easier it is to read the nameplate.

It may be an attempt to apply a "catch all" phrase as an answer, but a sawtooth generator is used to supply sweep. And sweep is used widely in electronics applications. One application might be in the search for signals in a given frequency band using a spectrum analyzer. That band, that group of frequencies, would have to be "swept" by the receiver. It would have to tune in the different frequencies in order and on a continuous basis. By applying a sawtooth wave to a voltage controlled oscillator (VCO) used as the local oscillator in a receiver, the frequency of the VCO could be swept up the spectrum from a starting point to an end point, and then it could be done all over again continuously. The correct sawtooth voltage to the VCO would enable the receiver to make pass after pass across the band under study, and the strength of a signal on a given frequency could be indexed and shown on a display.

"Phasing out" is a method to either check the phase shift across a transformer due to the winding characteristics or phasing to another transformer to ensure that the transformer is connected the same way. These tests usually apply to three phase Grid transformers.

Grid transformers can be wound in a number of ways. The simplist version is described as YY0. That is two Y wound three phase winding laid directly against each other. There is no phase shift ie 0 degrees. Other transformers can be wound YD that is a Y winding wound against a delta winding. Automaticallly there will be a phase shift across this winding.

Field test involve energising the high voltage side with a 3 phase supply. Voltages are then measured across windings. Ie measure the input voltage on Primary side Eg 230 Volts then measure the volts on secondary side between each phase to fill up a test table.

eg Rp Rs, Rp Ys, Rp Bs etc....

From these measurements it is possible by drawing a suitable vector diagram of each phase to show the phasing of each phase, the ratio and the angle of the transformation across the transformer.

An alternative (simpler) method is to use an oscilliscope from this superimpose the to voltages and measure the angle between them. It isn't so effective in the field with large voltages and not quite as accurate.

Lastly to phase the new transformer with the existing network measure the voltages of each phase to the corresponding phase on the network. The reading should be zero if youre phasing is correct and to confirm full phase voltage between phases.