Electrical Engineering

Use a transforer. The same is possible with European 230 volts to European 120 volts. If that should be necessary. US 220 volt service is simply two 110 volt cables connected to the same outlet.

Basic calculation is:

no. of cores x cross-section of one core x 9,6 = copper weight in kg/km

e.g. copper weight for cable 4x2,5 = 4 x 2,5 x 9,6 = 96 kg/km

This is how cable manufacturers calculate the copper weight.

Pls notice that it's valid formula only for cables without screening/shielding. If you know cross-section of screening, you can add that to the formula.

It varies by location and application. I will assume for this answer that we are talking low voltage (<1000 VAC): Grounded Wye Systems: 208/120 (Common) 480/277 (Common) 600/347 (Rare) Delta: 480 (ungrounded) 240/120 (grounded high-leg) 480/480 (corner grounded- rare and dangerous) The convention used above i.e. 208/120 designates the phase-phase voltage (208) and the phase to ground voltage (120). Some of the common Medium Voltage systems: 4.16 kV, 7.2 kV, 12.47 kV, 13.8kV

0 or if it a main breaker in a service entrance you can go down to #2

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A #3 copper wire with an insulation factor of 75 or 90 degrees C is rated at 100 and 105 amps respectively.

A micrometer is used to measure very small distances.

You could use a resistor, but you would need to know what the current of the circuit is. Use the equation;

R = V/I

R - Resistance

V - Voltage

I - Current

and divide the 3 volts (difference) by the current to get an appropriate resistor size.

The Quickest easiest way is going to be with a battery or jumper pack. Ground the body and touch the two terminals one at a time with the positive lead from a battery or jumper pack. One makes it turn the other makes it stop, the one that makes it turn is the starter or armature, the one that does nothing is the field. To go one step further to see if you are getting a good generator start it to full rpm and remove from the armature terminal and quickly touch the field terminal if the charging part is working correctly it should forcibly stop the pulley from rotating, you will notice a difference from just letting it spin to a stop.

The 555 timer is commonly used in IC electronics and in electronic circuits. In the monostable multivibrabor mode, the 555 works as a pulse generator. In astable mulitvibrator mode, the 555 is free running, and goes back and forth between frequencies.

There must be a 'return' connection if the load is to work. So, you cannot simply connect the load to the line conductor and expect it to work. It must also be connected to the neutral. In some circumstances (e.g. with no ground-fault interrupter installed), it will also work if you connect it to earth (ground) instead of the neutral, but this will contravene most electrical regulations and should NEVER be done.

EHV and VHV substations tend to have a signature hum; this is due to small electrical arcs. This is normal. Most of the time this will not be audible on VHV and EHV power lines. If you are hearing this from the power line, it could be bad and the utility may want to know. It shouldn't be a risk to you, however the hum may be resulting from arcing, which can be fairly high frequency, which can mess with electronics's signals such as cell phones and radio (won't damage them, just bad reception).

The formula you are looking for is I = W/E. Amps = Watts/Volts.

To get Watts you multiply Amps x Volts. So in your case you just do some reverse math and divide the Watts by the volts and you get your amperage.

so 100/120=0.83 Amps

A lot of things from metal to other stuff.

An ideal superconductor has exactly zero losses, thus resistance is zero.

They are each measured in volts (V).

The use of over load relays in circuits is to protect the circuit against over heating .

because the squirrel cage induction motor is cheaper and high starting performance is not required.

Reference points: Think about how the part will be made, and how it will be inspected. Usually something will make sense. Try to keep common references between drawing views, and if possible try to base everything from points, planes, or edges that appear in multiple views.

Tolerances: Consider how the part will be made- what minimum tolerances can be held on the intended equipment and processes? What is the maximum tolerance on the individual parts that will allow the assembly to fit together and function properly? The right answers lie between those extremes.

mcc - motor control center or motor control console.

A motor control center (MCC) is an assembly of one or more enclosed sections having a common power bus and principally containing motor control units

Phasor diagram is graphical representation of various electrical parameters in terms of their magnitude and angle.

Current is defined to be a flow of electrically charged carriers. These are usually electrons or electron-deficient atoms. It is symbolized by uppercase letter I.

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The invention of the capacitor varies somewhat depending on who you ask. There are records that indicate a German scientist named Ewald Georg von Kleist invented the capacitor in November 1745. Several months later Pieter van Musschenbroek, a Dutch professor at the University of Leyden came up with a very similar device in the form of the Leyden jar, which is typically credited as the first capacitor. Since Kleist didn't have detailed records and notes, nor the notoriety of his Dutch counterpart, he's often overlooked as a contributor to the capacitor's evolution. However, over the years, both have been given equal credit as it was established that their research was independent of each other and merely a scientific coincidence.

The Leyden jar was a very simple device. It consisted of a glass jar, half filled with water and lined inside and out with metal foil. The glass acted as the dielectric, although it was thought for a time that water was the key ingredient. There was usually a metal wire or chain driven through a cork in the top of the jar. The chain was then hooked to something that would deliver a charge, most likely a hand-cranked static generator. Once delivered, the jar would hold two equal but opposite charges in equilibrium until they were connected with a wire, producing a slight spark or shock .

Benjamin Franklin worked with the Leyden jar in his experiments with electricity and soon found that a flat piece of glass worked as well as the jar model, prompting him to develop the flat capacitor, or Franklin square. Years later, English chemist Michael Faraday would pioneer the first practical applications for the capacitor in trying to store unused electrons from his experiments. This led to the first usable capacitor, made from large oil barrels. Faraday's progress with capacitors is what eventually enabled us to deliver electric power over great distances. As a result of Faraday's achievements in the field of electricity, the unit of measurement for capacitors, or capacitance, became known as the farad.