answersLogoWhite

0

📱

Electrical Engineering

Electrical engineering is a field of engineering that deals with the study and application of electricity, electronics and electromagnetism.

23,056 Questions

How can a 24 v battery start a 80 kw emergency generator?

The 24v battery is used to provide the initial field current. This couples to the stator windings, and as the generator spins induces a voltage on the stator windings, which causes back EMF onto the field windings (when load is present), which slows the generator's spin until the governor kicks in to bring it back up to speed.

The important thing to note is the output power of the generator is not a factor of the 24v field voltage, it is directly dependent upon the fuel being used to get the generator spinning. The 24 volts just "jump starts" the field voltage. Think of it as synonymous with the 12 volt battery that starts your car.

Why transformer core is of magnetic not of wooden?

The transformer core is ferromagnetic in order to focus and concentrate the magnetic fields generated in the windings. This improves coupling and increases inductance.

Why dc output voltage of a bridge rectifier varies with the load current?

aA

A: the output of a Bridger's rectifier will always follows proportionally to the load since it does not regulate the output it merely transform AC TO DC

'

Why ordinary transistor is known as bipolar junction transistor?

Transistor is known as bipolar junction becoz it has 2 pole. Input is given to the 2 junction and output is taken from to junction

How does a dc generator differ from an ac generator in methods of working?

A DC generator has a commutator, a rotary switching system, that connects a different winding of the rotor, for each fraction of a turn. Thus keeping the polarity one way only. The stator windings are fed a proportion of the DC generated, to make an electromagnet. The power is taken off from the rotor via the commutator switching system.

An AC generator supplies the rotor with a DC current, via slip rings on the shaft, to exite it. (Makes the rotor an electromagnet) The power is taken off from the stator windings and alternates from one polarity to the other, as the rotor turns inside, producing AC and not having to go through a switching ystem.

What no load power factor 3 phase transformer?

The no load power factor would tell you the ratio of losses vs. excitation current. I'm not sure that this really has any value from a performance standpoint.

Answer

At no load, i.e. with the secondary windings open-circuited, the primary current, Io, comprises the magnetising current, Im, which is in phase with the flux and lags the supply voltage by 90o, and an iron-loss current, Io, which is in phase with the supply voltage. As Im is very much greater than Ii, the primary current, Io, lags by very nearly 90o. So, the power factor of a transformer on no load is approaching 0 lagging.

What is a bridgeable amplifier?

A bridgeable amplifier is a two channel amp where the two sections can be combined and used as a single channel amp with much higher (usually around double) power output.

There will be a switch or jumper that enables the bridge. Only one of the two inputs are used. The output is taken from the two positive terminals, one from each channel. The negative or common output terminals are not used.

A bridged amp fed from an electronic crossover is used a lot to feed a high-powered sub.

Current in a solid conductor is a result of movement in?

the current is actually a result of many factors. depending on the voltage type (AC or DC) it could be as simple as resistance in the circuit. when you are talking about AC circuits, there are also capacitive reactance (Xc), inductive reactance Xl), resistance, variances in voltage (fluctuations) , frequency... also the "skin effect" must be taken into account. solid conductors(especially at higher frequencies), are susceptible to eddy currents within the conductor itself. meaning that current just circulates withing the center, forcing EMF (electromotive force) to the outer "skin" of the conductor.

What is the resistance of an inductor called?

The resistance of an inductor is generally referred to as the series resistance, sometimes noted as RL.

Note that resistance is a DC measurement and that an "ideal" textbook inductor has an RL of 0.

The reactance of an inductor is an AC measurement which measures the reaction of a component's current flow to an alternating voltage and is frequency dependent and directly proportional to the inductor's inductance, measured in Henrie's.

The impedance is most commonly used when talking about inductors or capacitors and is a combination of resistance and reactance.

What is the REF 452 plus relay?

resistic earth fault relay install on transformer nutral .

What are the laws about repossession when payments are current?

This is one question that I had to get the answer to recently, and with the quickness! I learned that the laws governing the rules of repossession vary from state to state. You will need to look up the laws to find out your states terms and conditions. The lending bank's state of origin does not matter, it depends solely on the state the vehicle is registered in. Massachusetts requires

What is the difference between electrical circuit and electronic circuit?

One view point is that "Electrical" relates to the development and delivery of the electrical energy to the various devices that perform specific functions in a given environment. Example: The alternator in your car that series of wires delivers electrical power / energy to various components (radio, the computer that monitors / controls operation of the engine) in todays cars. Where as "Electronics" relates more to the complex functions performed within a given device, more often now days by circuits comprised of many micro electronic sub components that make up the structure of a single micro electronic component. Example: a typical CPU chip would / could contain thousands of individual transistor circuits within a device no bigger that the size of your small finger nail with room to spare.

Is the voltage in Dubai 220 volts or 110 volts?

Dubai uses 220 VAC at 50 Hz (in the USA, we use 120 VAC at 60 Hz). They also use the G type plug.

Electrons move from the power plant to homes in an alternating current?

Alternating current, yes. But it is not quite correct to say "electrons move to the homes... " rather, it is the CURRENT that moves to the home. It is more like a wave, where the energy is transmitted from one particle to the next.

Can a rheostat be used to control speed on a capacitor run motor?

No. If you attempt to reduce the voltage to a cap start motor by using a rheostat, you can destroy the motor.

What is The scientific word that means a unit of resistance to the flow of current?

The unit of electrical resistance is the "Ohm", written with the upper-case Greek Omega . . . Ω

Is it possible to synchronise two generators with no common electrical load to be exactly out of phase?

No, is it not permissible to synchronise two generators with no common electrical load to be exactly out of phase. Doing so would represent a double short circuit to both generators, and possible destruction of both generators. Whether it is possible or not depends on the design of the synchronizing circuit and/or the stupidity of the operator.

What current will transfer 96 500 coulombs in 1 hour?

1 hour = 3,600 seconds

96,500 coulombs/hr = (96,500 / 3,600) coulomb/sec = 26.8056 Amperes (rounded)

How do you know the air conditioner is going out?

you can either check that there is a smell

if there is a liquid bottle in your air freshner than see if there is any liquid left

Why does your Godard Sotexi 160 strobe constantly beep after one use?

if you are using a hotshoe cable or inexpensive RF remote to trigger the power pack it beeps after it fires once and you probably have to unplug the trigger cable from the power pack/camera hotshoe before it stops beeping and get ready for next flash.

the reason is that Godard 160 uses a higher level voltage (19 volts) and the hotshoe circuit does not dischage the current. if you ground the hotshoe it stops beeping and gets in ready mode.. I have not used the safe-shoe or pocket wizard with Godard so i'm not certain if these would help. however the guy i bought the strobe/power pack from had the safe shoe on his camera connected to power pack through com cable and it didn't beep

What is the current carrying capacity of a 3 core 70mm cable at 400 volts ac?

the current rating of a 70mm swa 3core cable is 1.2 amps buried or 2 amps on perforated cable tray suspended 500 feet above sea level in antartica

BMW 325e electric window circuit breaker reset?

Resetting Automotive Circuit BreakersWithout doing a "hands on" troubleshooting of your vehicle no one on this site can tell you specifically, what is causing the problem, or where to find it.

It has been my experience that all of the circuit breakers for automotive applications are self resetting.

Inside, they use bimetallic strips, and reset themselves when the circuit current overload, or short circuitconditions, has been removed/eliminated, and the bimetallic strip has cooled down.

IF your breaker is not resetting itself after a reasonable "cool down" period, then that suggests:

  • A short circuit condition somewhere in that circuit, or
  • An overload condition due to the addition of too much "extra" electrical equipment [like for example, a "monster" audio amplifier, or a light bar set], or
  • Replacement of an electrical device with one which uses much more current than the replaced device, or
  • A defective circuit breaker.