The term, 'unbalanced system' refers to an unbalanced load. Under normal circumstances, an unbalanced load leads to unbalanced line currents. The line voltages are determined by the supply and remain symmetrical, even when the load is unbalanced. As your question refers to a 'line to neutral' voltage (i.e. a phase voltage), you must be referring to a star (wye) connected load, in which case the phase voltage (line to neutral voltage) is 0.577 (the reciprocal of the square-root of 3) times the line voltage (line to line voltage).
What are the units and symbols for resistance?
Ohms is the unit of measure and the symbol is Omega which looks a bit like a horseshoe with open end pointing down.
What are the terms used in phase rule?
Any homogeneous system part of a system having all physical and chemical properties same throughout.
Explain the working of piezeoelectric oscillator?
A piezo-electric material is one who's physical dimensions (size) noticeably change when a current is passed through it. So if an AC (alternating current) is passed through a piezo-electric material, it itself alternates, or oscillates. This type of material is exploited in Electron Microscopes and Atomic Force Microscopes, which is how they are able to get such small, yet precise images.
Can you use three phase power for a dwelling unit service?
no
AnswerWhereas most countries have single-phase residential supplies, some countries, such as Cyprus, often have three-phase supplies. The main distribution panel ('consumer unit') must be designed and assembled to accommodate either a single-phase supply or a three-phase supply; you cannot use a single-phase distribution panel with a three-phase supply.
Why is the internal resistance of a voltage source made to be low?
When a voltage source, such as a battery or a generator, is on open circuit -in other words, when it is not supplying a load- the voltage appearing across its terminals is called its 'open circuit voltage' and corresponds numerically to its electromotive force.
However, when the voltage source supplies current to a load, that current also passes through the voltage source itself. This causes an internal voltage drop, which is the product of this current and the voltage source's internal resistance. This voltage drop acts in the opposite direction to the electromotive force and reduces the source's terminal voltage. This internal voltage drop will increase, of course, if either the load current increases or the internal resistance increases.
So, in order to keep that the source's internal voltage drop is as low as possible, its internal resistance must be as low as possible. In the case of a battery, the internal resistance is due to the ionic resistance of the electrolyte/plates, whereas in a generator it is due to the resistance of the windings.
Overloaded circuit, short in circuit, or defective switch.
Why we use rms value of current why not simple value of current?
RMS (root mean square) is often used as opposed to the peak to peak value because it expresses the actual power for AC systems. For example, your actual home voltage is closer to 170 volts peak - neutral. Say you have 1/2 Amp peak -neutral current flowing. Actual power is equivalent to:
P = Vrms*Irms; RMS = Vpeak-neutral/sqrt(2)
P = 1/2 * (Vpeak-neutral) * (Ipeak-neutral).
You can quickly see that discussing wire size, fuse sizing, breaker sizing, etc. in terms of peak - neutral or peak- peak volts / currents, will quickly become more complicated than it needs to be.
This is also a more useful value from a usage standpoint, as you will be charged for the power you use.
Single phase AC motor winding formulas?
Single-phase motors efficient because the circuits are less complex; fewer electrical steps must be taken to achieve a desired output, so less power losses , how ever efficient=P(out)/P(in) , P(out) which more related for power losses as heated ,iron losses, stray losses and mechanical losses.
What does a parallel circuit do?
A parallel circuit has more than one resistor (anything that uses electricity to do work) and gets its name from having multiple (parallel) paths to move along . Charges can move through any of several paths. If one of the items in the circuit is broken then no charge will move through that path, but other paths will continue to have charges flow through them. Parallel circuits are found in most household electrical wiring. This is done so that lights don't stop working just because you turned your TV off.
What is compliance limit voltage?
Compliance voltage is the voltage available at the counter electrode that can be used to force current to flow and still maintain control of the working electrode voltage. The compliance should be specified in conjunction with a current value: "20V @ 200mA" or "20V @ full rated current". An amplifier's output voltage decreases at higher currents due to the output impedance of the amplifier.
The voltage at the counter electrode is needed to force the electrochemical reaction at the counter electrode to proceed and to overcome the iR drop through the bulk of the electrolyte solution. Compliance voltage can become important when the currents are high, or when the conductivity of the solution is low (dilute electrolytes), or when a high resistance sintered glass or Vycor frit has been used to isolate the counter electrode.
In practice, depending on the electrolyte and cell design, the potentiostats useable limits may be defined by either its maximum current specification or its compliance voltage limit. In either case, if the limits are exceeded the potentiostat will be unable to properly control the voltage of the working electrode.
Example for testing compliance voltage
Construct a "dummy cell" with the following resistors, and connect the leads of the potentiostat as shown:
This is representative of a cell with electrolyte of low conductivity. As the reference electrode is generally placed closer to the working/sense (the junction across which voltage is controlled and/or measured depending on potentiostatic or galvanostatic control, respectively), there is less impedance than between the counter and working/sense.
Request the potentiostat to apply a 5V potential (i.e., a Chronoamperometry experiment), and you will see a current of 5mA current (as expected).
Can you amplify the electricity when you have only very small power supply or any mechanism for it?
you really can't amplify electricity. You can amplify sound but that is different. You can change the voltage but the actual power will not change because as voltage is raised current is reduced. you can only increase power by increasing the mechanical input to a generator which will increase the electrical power as well. The conservation on energy says that power cannot just be created. It needs to come from some where either mechanical or thermal.
Following the conservation of energy, you can convert kinetic energy into electric energy using a (relatively) small amount of electricity - this is what a synchronous generator does. A small amount of electricity is used to create a magnetic field; the stronger this field, the more energy can be "pushed out" of the generator; this energy must come from the kinetic energy stored in the spinning machine. In this way, a synchronous generator can be thought of as an electricity "amplifier".
Why can't voltage become zero when resistance is zero?
By Ohm's law, voltage is directly proportional to current. You question seems to be missing some detail. Are you talking about an AC dircuit where there is capacitive or inductive reactance present? If so, please note that Ohm's law still applies, but things are a bit more complex with AC and inductance because you now need to consider voltage to current phase angle, as well as how you are measuring things. Please clarify your question.
Examples of embedded system development?
embedded system is an electronic device which is made for an specific task.when we are taking about the embedded system development.it include the embedded life cycle,in which we have to specify the product ect,up to maintanence
Why ampere is base unit if it is derived from charge?
The ampere is the SI Base Unit or electric current. It is NOT derived from the charge (coulomb) but from the force resulting from its magnetic effect. The ampere is defined in terms of the force between two, parallel, current-carrying conductors due to the interaction of their magnetic fields. The coulomb, on the other hand, is an SI Derived Unit, based on the ampere and the second.
What is the effect on the supply current if the capacitor removed?
It depends on how the capacitor is connected and whether the supply voltage is a.c. or d.c. Assuming you are talking about a power-factor improvement capacitor (connected in parallel with an inductive load, supplied with a.c.), then the supply current will reduce.
What is the function of a silica gel in a circuit?
Property of Silica gel is to absorb the moisture. Colour of dry silica gel is blue and it turns into pink when it is saturated with moisture. When the colour of silica gel turns out pink, the wet silica gel is removed and the fresh silica gel is filled. The wet silica gel can be heated and made dry for reuse.
What elements in a curcuit can change eletrcical energy into other forms of energy?
Resistance converts electrical energy into other forms of energy, such as light, heat sound, motion, and magnetic effects.
A diode converts AC to pulsed?
If you put a diode in series with an AC sine wave that goes plus and minus, it will cut off either the positive or negative portion of the waveform, depending on the direction of the diode in circuit. So in effect you have a pulse equal to one half cycle of the sine wave.
Can you Show diagram of 3 phase motor circuit?
Connect the three wires that come out of the motor to the three supply wires that come from the magnetic contactor. Turn the power on and push the start button. If the motor turns the wrong way, shut the power off and change any two wires in the motor junction box.
What is the reason of reverse indication on in single phase kWH meter?
A kWh meter measures the flow of energy along the circuit that the meter is connected to. Normally power flows from the supply to the load, which is the conventional direction, but in some cases, for example if the load is replaced by a generator, power can flow the other way and in that case the meter indicates a backward, negative, flow of power.
What connection is the higher ampere between delta and wye?
For the same load, delta provides higher current than wye, or star.
Wye voltage is 1 / 1.732, or 0.577 that of delta. (1.732 is the square root of 3.) This gives a power of 0.333 for wye, as opposed to delta. (0.5772 = 0.333)
This is why (no pun intended) we use wye-delta starters on large motors - it allows them to come up to speed at 1/3 power, before switching to full power on delta.
How is an ammeter connected to reduce frequency errors?
Connecting an ammeter does not reduce the frequency errors.
Zero amps equal one volt. To find amperage you need one of the following formula I = E/R, I = W/E or I = to the square root of W/R.
I is amperage, E is voltage, W is watts and R is resistance.