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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
The symbol for a diode is a horizontal line with an arrow pointing to an intersecting vertical line, the horizontal line continues on the other side of the vertical line.
What is the line diagram symbol for a mercury tilt switch?
The diagram symbol for any tilt switch is the ball tilt switch symbol.Then in the table of contents the switch is described,whether it be a ball switch,mercury switch,etc...
What does mva stand for in the turbo generator field?
There are two concerns here regarding loading on transformers of this size. First is the difference between MVA and MW. MW is just real power -- watts. MVA is total power which includes real power (MW) and reactive power (MVAR).---
http://en.allexperts.com/q/Electric-Power-Utilities-2405/operation-limit-oof-power.htm
Where does the supply authorities cable enter a building?
find your electric Meter and you've found the point of entry, or depending on where the electric meter is in the building, you can trace the cable back from the meter to the point of entry.
AC stands for alternating current and means that the current changes directions, flipping repeatedly from positive to negative and back again.
DC means direct current, the current only flows in one direction and does not change polarity.
Why doesn't the primary winding on a transformer have a neutral?
In a three phase transformer, the primary winding is often configured in a Delta. The delta winding configuration does not use a neutral. The secondary winding is often in a Wye configuration, which does have a neutral.
The Delta configuration is typically used for transmitting power to various locations, and thee phase loads where a neutral is not needed. The Wye configuration is typically used to distribute power in a facility where there are single phase loads that need a neutral.
There are other reasons to use either Wye or Delta, such as grounding issues, but I think the short answer is probably what you're looking for (I hope).
Hope this helps!
Dave
Why is the electric watt meter connected in series with the rest of the circuits in the house?
First of all, you are referring to an energy meter, not a wattmeter. A wattmeter measures power, in watts, whereas an energy meter reads energy, in watt hours (or, more specifically, kilowatt hours). The energy company bills you for energy, not power.
Having said that, the connections each instrument are the same. In fact, there are two coils inside an energy meter: a current coil, and a voltage (or potential) coil. The current coil is connected in series with the load while the voltage coil is connected in parallel with the supply voltage.
The current coil measures the in-phase component of the current drawn by your load, so that the instrument always reads the true power (multiplied by time -the function of the aluminium disc) of the load -i.e. not the apparent power or reactive power.
What generator size for twin 150 hp 480 3 phase motors 800 amps for a tire shredder.?
First of all, a 150 HP 460V 3-phase motor only draws around 170A, so two of them would only draw 340A, not 800.
340A at 460V equals almost 300,000 watts (or 300kw), and the generator would need to be sized a little bigger than this to start such big motors.
Since when has fixed capacitor have been seen in use on transmission line?
Capacitors have always been added on both power lines and telephone lines to compensate for the build up of inductive reactance in long runs of wire.
What can protect a computer from problems caused by a change in power?
- A surge suppressor will protect against transient high voltage surges.
- A ferroresonant transformer will protect against transient low voltage brownouts.
- A uninterruptable power supply will protect against power failures of several minutes duration.
What is the theory of converting electrical energy into heat energy?
Electricity does work (W =I2Rt) ) on a conductor, causing its internal energy (U) to rise. This rise in internal energy is accompanied by a rise in temperature, resulting in heat transfer (Q) from the conductor to the surroundings. It should be pointed out that the term 'heat energy' is no longer used -heat is simply energy transfer caused by a difference in temperature.
What are the advantages of three phase to two phase electric power distribution systems?
Polyphase systems are used because they allow the efficient transmission of electric power, in terms of power transmitted per kilogram of wire.
Polyphase systems with more than three phases are very uncommon.
Which cicuits light the bulb better-Bulbs light better in which kind of circuits?
If you are comparing parallel vs series circuits, light bulbs produce more light in parallel circuits.
The power developed in a resistor of 24 ohms is 225watt what is the current?
Ohm's law states V = I*R, and power is equivalent to voltage times current, so a little manipulation will get you to:
P = R*I^2
225 = 24*I^2
I = 3.06 amperes.
Can you replace a 2-30 trimmer capacitor with a fixed value capacitor?
Yes you can.
But the variable one is used so that you can very the frequency and it cant be varied anymore if you use a fixed capacitor.
It's called a 'distribution transformer', as opposed to a 'power transformer' which is used in the transmission and primary-distribution electrical systems.
Where can you buy a galvanized nail?
At home depot or maybe at your closest dollar store, they have a lot of different types of nails, but be careful what they say because they might be screws instead.
Does a hollow metal tube conduct as good as a solid rod of the same material?
as in solid rod there has more free electrons which will cause more current than a hollow metal tube of same dia/length/material.
How do you convert capacitors to resistors?
Capacitors are completely different than resistors and there can be no converting between them, whatever that means.
How do you wire a two speed pool motor?
Your pool control system must be capable of handling a two speed motor. You'll have to go to the manual to determine connections for your specific motor and controller. You can't effectively use a two speed motor if your control system is not designed and programmed for such a motor.
