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Electrical Engineering
Electrical engineering is a field of engineering that deals with the study and application of electricity, electronics and electromagnetism.
23,056 Questions
Will a hair dryer suck instead of blow if the fan blade is turned around?
A: That will be true ONLY if the blades have a pitch to it
What cause high reflected power in transmission line?
Poorly matched terminating impedances will result in high reflection. Tuning networks on both ends are used to tune the source and load to the same impedance as the transmission line.
Grounding terminals are used to connect the electrical equipment or wiring system to the Earth. It's purpose is to reduce the risk of electrical shock in the event of a fault current. In most homes, the wiring system is permanently grounded to a metal pipe that connects to an underground water-supply system or to a metal rod that has been driven into the ground.
How does the starting of synchronous motor using dc generator as a load work-?
Starting of the synchronous motor using the DC generator creates a magnetic field.
Is it easy to make electricity using natural gas?
Slightly easier than with coal or wood, because it's easier to pipe gas from the
well to the burners, and when natural gas burns, there's no remaining ash that
has to be shoveled out. But all of them are equally efficient at belching carbon
into the atmosphere, and equally desirable sources of heat with which to boil
water to make steam to turn a turbine to turn a generator.
What are the benefits of a PhD in electrical engineering?
Your more likely to get a job, and you will probably get paid more for it.
no, the transformer is much more efficient
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HOWEVER- a transformer only changes the voltage of AC current- it does not change it to DC. You will still need diodes or rectifiers. You can also use a motor/generator- a 230v AC motor turns a 12 v DC generator.
Where could one purchase a frequency generator?
It is not as well known as it should be, but some outlets where one can purchase a frequency generator would include internet sites, hardware stores, or local specialty stores.
The main test instrument is called a megohm meter, megger for shortened version. On the whole megger testing is non destructive. What happens is a DC voltage is applied to the device or winding under test. It is an insulation test to see is the insulation has been injured in any way to cause a short circuit when normal power is applied to it. On my megger there are 3 ranges 300V, 750V, and 1000 volts. Applying the proper voltage is essential to not damaging the device you are testing. Working voltages up to 240 volts should use the 300 range. Working voltages up to 600 volts use the 750 volt range and working voltages above 600 use the 1000 volt range. As you can see if you used the 1000 volt range on a device that had a working voltage of say 24 volts you could damage the insulation just by testing it. So meggering a device is non destructive if you use the tester as its instructions tell you to.
I am assuming that your batteries are 12V, also that your (12V - 240V) inverter is rated for 5KW output and it is about 95% efficient. Most big inverters are between 85% - 97%. 5KW from a 12V battery would mean a current draw of about 416A, but since the inverter is only 95% efficient the actual current would be closer to 438A. If you draw 438A for two hours, that's 876AH. Theoretically then, you would need 9 100AH batteries. The problem is that at very high current draw, all batteries AH capacity is less than the rating. You only get the whole 100AH if the current draw is 10A (1/10th the AH rating) or less. Because of that, you would probably need 10 to 12 batteries. If you used 10 batteries, each would source about 44A during full load. You would have to use very large bus bars to equalize the current draw from battery to battery. If the interconnects are too small, the batteries closer to the inverter would be forced to supply more than their equal share of the total current draw, and the ones further away less. It's generally problematic to parallel large numbers of batteries in this way. Don't even consider it unless the batteries are identical (same manufacturer, same part number, same age, same date code). The problem gets even worse when you try to recharge the pack. Suppose you pump 50A of charging current into 10 batteries. Is each battery receiving 5A? Or is one battery with a shorted cell drawing all 50 (and is about to explode...)? There's no way to tell. Even if all batteries were receiving equal charge, it would take your 50A charger almost 40 hours to recharge 10 - 100AH batteries. Ouch. Large industrial UPS systems get around this by using huge 2V cells in series. You can buy 6 - 2V, 1000AH cells, connect them in series to form a 12V, 1000AH battery and avoid all the hassles of parallelling 12V, 100AH batteries. They are not cheap, though. If you go to a battery manufacturer's website, they publish graphs for their batteries that show AH derating versus current draw. All this assumes, of course, that your load is really 5KW. If you are running a smaller load, then obviously your battery count would go down. Finally, we are talking extremely large current and power levels here. If you are not fully qualified to understand and design high current wiring systems, don't try this! 400A of current through a bad connection can do serious damage! Unless you enjoy being sprayed with molten metal from a disintegrating connection, know what you're doing or get a qualified individual to help with/inspect your work. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB
SAFELY AND COMPETENTLY
REFER THIS WORK TO QUALIFIED PROFESSIONALS. If you do this work yourself, always turn off the power
at the breaker box/fuse panel BEFORE you attempt to do any work
AND
always use an electricians test meter having metal-tipped probes
(not a simple proximity voltage indicator)
to insure the circuit is, in fact, de-energized.
Putting capacitors in series and then applying a DC voltage to them is not entirely useful. The voltage will cause a small current to flow into the capacitors, charging them to a total cumulative voltage of 200V. No further current will flow. If a meter is applied to one of the capacitors it's charge will cause a voltage measurement but it will quickly drop as the current flowing into the meter discharges the capacitor.
You will be able to find this flow chart online. Make sure to find one that has all of the parts labeled to help with studying.
What is a super luminescent diode?
With their emission properties Superluminescent Light-Emitting Diodes (SLEDs) are closing the gap between Laser Diodes (LDs) and Light Emitting Diodes (LEDs).They offer the broadband optical spectra of LEDs and the spatial coherence of LDs. Compared to Laser Diodes and LEDs, SLEDs can be understood as • Spatial coherent broadband laser diodes with a beam-like output
• Temporal incoherent laser diodes with a broadband spectrum
• Speckle-free laser diodes with a short coherence length
• Spatial coherent LEDs with a beam-like output
Process of installation repair and maintenance electrical systems?
Electrical basics Get a job with someone knowledgeable, as a helper, for about five years, attend electrical classes at night, read every technical manual you can secure and learn the various electrical codes.
That should provide a rudimentary understanding of what is required.
Do transformers use steady magnetic fields to produce an emf in the secondary?
In an AC circuit it is the fluctuation of the sine wave which causes a varying magnetic field which in turn induces a current to flow in the secondary.
How do you make a wet cell battery with coins?
You will need 5 copper coins witch are pennies and 5 non-copper coins witch are dimes, pieces of paper towel and lemon juice.
First you take a piece of paper towel and dip it in lemon juice. place it on top of a copper coin. then you take a non-copper coin and place it on top of the paper towel. After, you take a piece of paper towel and put it on top of your non-copper coin. Do the same thing as a pattern until you have used 5 copper coins and 5 non-copper coins. Make sure you have a piece of paper towel in between each coin. Finally, wet each finger tip and hold the ends of your battery. Do you feel a BZZ?
What is the relationship between resistance and current in a resistive circuit?
:) It's connected together
The IN5408 diode is an ordinary silicon diode. It has a 3 amp forward current rating, and a 1000 volt peak reverse voltage rating.
Frequency of emf generated per rotation of rotor is equal to?
The frequency of emf generated per rotation of the rotor depends on the number of poles on the rotor and on the field. Please restate your question.
For the two pole / two pole case, an atypical configuration, but good for illustration, 3,600 RPM would generate 60 Hz.
How many parts in a transformer?
The basic parts of a transformer are the core and the windings.
However practical transformers often have many more parts:
- the core could be solid or composed of possibly hundreds of laminations
- the windings could be wound directly on the core or on one or more bobbins
- a shield may surround the transformer
- a mounting frame may be used to assist in mounting the transformer
- several solder lugs will usually be provided to facilitate connection to the circuit
- etc.
Why synchronous motor is called synchronous capacitors?
A synchronous motor can operate as either a Generator or a Motor.
When a synchronous motor has current applied to the windings on its rotor and the stator is energized with say a 50hz line supply (with little or no physical load) then the exact amount of excitation provided by the rotor can determine whether the stator displays inductive or capacitive properties.
If the rotor is under excited (too Little rotor current) the Synchronous Motor will behave as an Inductor, however if the rotor is over excited then the Synchronous Motor will behave like a Capacitor.
Hope this helps
Divide the amount of turns in the secondary into 32 V and you'll get 8. Now multiply 8 times 60 turns and you'll get 480V.
No electrical power to blower motor 1990 Cadillac eldorado?
So whats the question WHY? Could be a bunch of things. How about checking the fuse first.
Will there be a transformers three?
In Wikipedia It Says That Shia LaBaouf Signed Up For 3 Movies. It Means That There Is Going To Be A Third Movie.
