Electrical Engineering

The nearest AWG wire size to 50 sq. mm is 1/0.

A 1/0 aluminium conductor with an insulation factor of 75 or 90 degrees C is rated at 180 and 205 amps respectively.

in FV analogy, mass is analogous to inductance

A universal motor is used to operate a food mixer.

A generator is a electro-mechanical device which converts kinetic energy into electrical energy. The basic concept is when a wire passes through a magnetic field, it causes the electrons to flow perpendicular to the field. Remember the right hand rule? If your fingers are in the direction of the field, your thumb is the direction of electrical current. Depending on the type of motor, the rotor (shaft) and stator (houses the rotor) will contain the wires or magnets. A motor is no different then a generator as it provides the kinetic energy by applying electrical energy.

For measuring electrical Current the electrical equipment used is Amphere meter. This equipment tells the current flow in the equipment.

You must know the applied voltage to determine the answer. According to Ohm's law:

I = E/R (current equals voltage divided by resistance)

So, if the voltage were, say, 16 volts, then the current through the 8 ohm resistor would be two amps:

2 = 16 / 8

There are actually three pieces to this puzzle - resistance. And you're missing that one.

How to Read Your Electric Meter ---- It's no mystery! Your electric meter can easily be read if you understand some basic rules. Each of the five dials represent one digit of the present reading. As you can see, the dials move both clockwise and counter clockwise. When the hand of one of the dials is between numbers, always take the smaller number. For example: 4 6 3 7 2 If you cannot tell if a hand is past a number or not, simply look at the dial to the right. If it has passed zero, then the hand is pointing to the correct number. If the dial to the right has not passed zero, then use the next smaller number. Totally confused? Let's try an example: 4 6 3 9 2 The third digit is a three because the digit to the right has not yet passed zero. If the second dial from the right was between the zero and the one, then the third digit would have been a four. Easy isn't it! To practice, go outside to your home or business and record the readings for several days in a row. By subtracting yesterday's reading from today's reading, you can get a feel for how much energy (kilowatt hours) you use each day. Keep in mind that when the power company representative reads your meter, they do NOT set it back to zero. Therefore the dials keep turning until the next time the meter is read. By subtracting two consecutive readings, the amount of kilowatt hours is determined for the month. Greeneville Light & Power System personnel use hand-held computers to record the meter reading. The computer immediately checks to see if the reading is about the same as the one the previous month. If it is quite a bit lower or higher, the meter reader is asked to re-read the dials to make sure the reading is correct. This helps insure your bill is accurate each and every month!

The current in the circuit will be decreased by half. Ohm's law states V=IR so, I=V/R. If R is doubled, then I= V/2R.

this is a question with several differant answers..... depending on consuption if its going on a consuming structure co-generating or a stand alone generation station. the most cost effective would be a hybrid thermal/photovoltaic the thermal would heat a closed contained liquid and make steam to turn large turbine. $150,000US will get u quite the little generator. $1,000,000US u have a major player my general rule is $15us per sq ft of heating/cooling space. I am presently puting together the single largest solar project of its kind. entire subdivisions of low cost modular homes with the entire roof as the mini-generating station. so if u put up say 400 units. when this hole subdivision comes on line u have a major Generating Station. maitaining a plant with no moving parts to wear-out, well except to send some one to clean the panels off once every 6 months wound not be much up-keep...... the panels have 20 to 25yr warrenties and 30yr life some put up in the late 60's r still generating. JD Polk, founder&ceo

Alternative Resource Electric Corp inc

(solar,wind & tidal-flow generation one platform)

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904.333.9814

888.448.9188

cell 904.525.POLK

The ampere frame rating for a circuit breaker designates how the circuit breaker should be configured. It also states the trip unit of the amp.

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A teriary winding is useful for many things. A delta tertiary will help balance voltage/currents to some degree. It also traps third harmonics. In substations, the substation power is often taken from the tertiary. It can also be used as a lower voltage connection for inductors (much cheaper, due to the lower voltage vs. primary connected inductors).

No. They are connected in parallel with each other.

The formula is 1/(j*w*C), where j is an imaginary number (this makes it reactance, not resistance), w is the frequency in radians, C is the capacitance.

If you want a proof of this, you should look at wikipedia under laplace transform. I'm sorry, the proof of this is probably not what you would consider simple or easy, if this is what you're looking for. It is based on calculus, and I know of no way to get around it.

240 volts is a typical single phase voltage (one phase wire and one neutral wire, possibly a ground wire as well) while 208 is a three phase voltage (you will have three phase wires, plus possibly a neutral wire)

208v in a grounded system is actually 120 volts referenced to ground. That is, there are three 120 volt voltages referenced to ground 120 degrees apart.

A typical house will have 120 and 240 volts. These are both single phase, but the utilitiy company's transformer providing this power has a center tap - so three wires from it, one at 0 volts (the neutral or return - usually the center), one at 120 volts, and one at -120 volts referenced to ground.

OC and SC tests are used for predetermining the efficiency and % voltage regulation. It is more efficient test for a transformer than sumpner's test for 2 reasons.

1. two identical transformers are readily not available

2. two separate power supplies are required for the sumpner's test, whereas OC and SC are simple and best

capacitive start motors start by themselves however a normal single phase induction motor requires a starter motor to 'kick-start' the motor into action.

When discussing harmonics in relation to transformers, generally you're thinking of harmonics in the current waveform - if it's a 60Hz transformer, the 2nd harmonic would be 120Hz, and is usually very high on transformer energization (referred to as inrush current). The nonlinearity of the core can result in core saturation under multiple different conditions, which tend to produce harmonic currents.

You apply a voltage across a load and the result is that a current flows through the load. So you must have the voltage present, the cause, before current flow, the effect. Think of voltage as pressure and current as flow.

Voltages are induced in the sheath of cables running in parallel which result in circulating currents flowing in the sheaths. The distances between single core cables running in parallel determine the voltages induced. With single core cables in trefoil formation (touching each other) the distances between the cables are minimum and thus the voltages induced are minimised and hence the circulating currents.The circulating currents cause localised heating.