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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
Can you use the vacuum circuit breaker instant of air circuit breaker?
Actually ACB isused for Low Tension side and VCB is used for High Tension Side..Chappa matter
What is the rule of thumb for cable size selection?
It is not that easy. There are several steps to finding the correct cable for a specific load. It largely depends on the type of cable, the environment to be installed and the supply characteristics. Only a trained licensed electrician or electrical design engineer could do this safely. There's no simple rule of thumb. <><><>
As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.
Before you do any work yourself,
on electrical circuits, equipment or appliances,
always use a test meter to ensure the circuit is, in fact, de-energized.
IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB
SAFELY AND COMPETENTLY
REFER THIS WORK TO QUALIFIED PROFESSIONALS.
Many times the plugs at the ends of the adapter will be different for different voltages and mA ratings. If it is the same, then look at your device (or the user manual.) It should give the input voltage and current ratings. If the amp draw of the device is greater than 300mA, do not use the ac adapter. It will damage the adapter and could damage your device. If the tuner came with a 800mA charger, then I'm sure you should go buy another for a few bucks at an electronics store.
What is the working principle of a TDS meter?
1)what is the relation of total dissolved solid and conductivity of water?
2)What is the difference of the conductivity of treated water and raw water?
How does the computer get its electricity?
Most computers use a mix of battery power, as well as electricity, as their energy source. For instance, your cell phone works through battery power that you must charge with electricity when it runs out.
Why does the surge protectors circuit breaker trip if a surge or overload is detected?
A circuit breaker shuts off the power to an electrical circuit when it detects too much current flow. As electricity moves through wiring, an electromagnetic field develops around the wire. Electromagnetic breakers capitalize on this field production by using electromagnets. The current that moves through the breaker charges the electromagnet and as the current increases the magnetic pull also increases. If the current exceeds the limit the breaker is designed to handle, the magnetic pull becomes strong enough to pull the contact plate away from the stationary plate. This breaks the circuit and is referred to as "tripping the breaker.
A surge protector on the other hand prevents a voltager higher than the normal voltage from damaging electical devices. It does not shut off the power as a circuit breaker or fuse does.
Is delta connection also called a star-star connection?
the delta has a higher voltage to ground on the B phase and is identified by the orange color for identification means so its easier to smoke equipment if not careful.hardly see delta connections anymore so old school and outdated. it just makes economic sense to use a star connection.
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On the above answer there should be no voltage to ground on a delta connection. All three phase coils are connected in series with each other and at no point in the delta are they grounded. Most of the commercial and industrial motor connections are connected delta. In installations where the motor inrush is above utility company specifications the Star- Delta connection is used. This limits the inrush current in the star configuration and then after a time delay connects the motor in a delta configuration. With delta systems the use of grounding lights are mandatory. These are used to detect if a phase grounds out. One phase and the motor can still be in operation, two grounds represent a short circuit and the system will trip.
CommentThe second answer is not altogether correct... In the USA and Canada, it is common practise for one phase of the delta-connected secondary windings of a three-phase transformer bank, to have an earthed (grounded) centre tap. With each phase providing 240 V; the centre-tapped phase then provides a combination of 240 V line-to-line together with two 120-V line-to-neutral (earth) voltages which is the standard supply method for residences in North America. The point of common connection between the two remaining phases is termed the 'high leg' of that particular transformer connection, having a potential of 208 V with respect to earth (although this is not used). To summarise, this method provides a 240-V three-phase supply, combined with a single-phase 240/120-V supply, which is useful for small businesses (e.g. garages) which might need to operate three-phase motors.
However, the second answer is perfectly true for the UK (and, possibly, elsewhere in Europe) where residences are supplied with just one voltage (230 V) -unlike North America- and delta-connected supplies are relatively unusual.
How many amps can you draw from a 25kva 3 phase step down transformer?
For practical purposes, transformers do not lose power during transformation. Thus, if you have the VA of the transformer, you can simply divide the VA by the voltage to get a rough idea of maximum current.
In a real application, the maximum amperage will be dependent on the phase angle of the transformer.
Why is the motor of the transformer locked?
The only motor associated with a transformer is an on-line tap changing mechanism motor! So your question doesn't really make any sense!
What are the characteristics of a sine wave of voltage?
Some of the three characteristics of a wave that can be measured include the frequency, wavelength and amplitude. The amplitude would correspond to loudness in sound waves and brightness where light is concerned.
What is corona effect in electrical?
When the distance between two conductors is more than that of the diameter and the potential difference is increased beyond the certain limit in such a way so that a glow ( seems like violet and shine ) is produced around the conductor and also noise is produced. This kind of effect called the Corona Effect in power systems.
As the potential difference is increased, Corona Effect is also increased, and due to Corona Effect, Power loss in power system and disturbance in the nearer communication line is also increased.
What is grounding - grounded - neutral?
A) If low resistance configuration is chosen, then, ground fault current is greater than 25% of 3-phase value.
B) If high resistance configuration is chosen, then, ground fault current is between 1 to 5% of 3-phase value.
C) Ground fault protection scheme is important because affects resistor thermal rating, hence size.
D) For B) above, ground fault current must not be less than system charging current produced by phase to ground capacitance in 11 kV system.
E) For D) above, total capacitance calculation must include line to ground capacitance of cables, motors, transformers, and (often forgotten) surge protection capacitors, as well as lightning arrestors. shirish prajapati
What is an electrical fuse-tester?
a multimeter. you are testing for continuity, in other words if see some resistance the fuse is no good. you are looking for zero resistance, or a short. a multimeter. you are testing for continuity, in other words if see some resistance the fuse is no good. you are looking for zero resistance, or a short.
How many amps will a 10 kva transformer handle?
It depends on how many amps it was designed for. A 12.5kV/600v 10kVA 3 phase transformer can handle ~.5 amps on the primary and ~10A on the secondary. A 600/120V 10kVA 3 phase transformer can handle ~10A on the primary and ~50 on the secondary.
What is the advantage and disadvantage of using thermostat in an iron?
The advantage of using the thermostat is so you don't burn or scorch your clothes when you are using it. An iron can become very hot quickly.
Can candles and magnets produce electricity?
I can think of two ways to do that:
1). Place a burning candle near a photovoltaic (solar) cell. The cell will convert
some of the heat and light energy from the candle flame to electrical energy.
2). This one is more complicated and takes more ancillary peripheral stuff.
-- Use the burning candle to heat and boil a container of water.
-- Guide the steam from the boiling water through the fan of a small turbine generator.
Is current equals voltage divided by resistance series circuits parallel circuits or both?
Ohm's law: Current equals voltage divided by resistance.
It does not matter if the circuit is series or parallel or both. Ohm's law still applies. What you do need to consider is that it applies for each component on its own merits. The is one of the fundamentals of circuit analysis, the progressive analysis of each component, taking account of what you know for that component, until you know everything about all components.
What the transformer oil transformer provides?
Significantly-better cooling and insulation than air. This means that the transformer can operate at higher power ratings than an equivalent air-cooled transformer, and its internal electrical components can be much closer together, giving an oil transformer a much smaller footprint so it takes up far less space in a substation.
What is mean by burden of the current transformers?
The burden on a CT is the sum total impedance connected to the secondary - including the CT secondary winding coil resistance, lead resistance, and any loads attached (relays, meters, etc.).
If this is for power calculations and CT saturation in three phase systems, remember you must multiply the lead resistance by two to get the total path resistance.
Another Answer
We use the word, 'burden', to describe the load supplied by the instrument transformer's secondary. This is normally a measuring instrument or protection relay. We use the word 'burden' to distinguish it from the 'load' supplied by the circuit to which the primary winding is connected.
What is the formula used to determine the maximum allowable amperage for a given circuit?
There is no single 'formula' for this, as the maximum current a circuit can handle depends on the temperature the various components within that circuit can operate at, without deterioration. There are so many factors involved, such as the type of component, the type of insulation, whether it can cool naturally or whether it must be force cooled, etc. Every circuit must be considered on an individual basis.
How do you store direct current?
DC can be produced in a battery via a chemical reaction. Also solar panels can produce DC directly. If you have Alternating Current (AC) you can convert to DC using a full wave bridge and filtering output.
What size cable will you need for a 1000kva genset?
You can use 5Rx 3.5 C x 240 sq.mm Al. Ar. XLPE cable ... or 6R x 3.5.C x 300 sq.mm AL. Ar. PVC cable -
S.Ramamoorthie
MEP - HEAD
Bangalore
What features make Maglev trains economical?
- to make it go faster the wheel support path will help it and the propulsuion coil will help it
