Electrical Engineering

capacitor is component used to store and release the electric charge.and also it has feature to block the dc but bypass ac.and inverter is device which converts ac to dc and then again ac

depends on what you are measuring

practical use like electricity or batteries as low as possible

to test voltage on a car battery perhaps 0.1 ohm / volt

to check the final anode on a crt tv at least 1000 ohms per volt

low power circuits require higher impedance

wire connections low impedance

the 10000 ohm per volt meters are fine as fixed monitors but usless for practical service work. they indicate voltage thru oxides and lose screws

they show 120V in a socket when the lamp refuses to light

480V about 20A

240V about 40A

look at the nameplate

duty cycle and efficiencies vary

We will always calculate rms value only since the average value of ac current or voltage is zero. So we are using rms values in the ac circuit to calculate the power and to solve an ac circuit.

With the possible exception of a variable reluctance transformer, you should always avoid core saturation of any type of transformer.

When saturated the magnetic characteristics of the core material is radically changed and the coupling coefficients will be very different. Additionally, many transformers can overheat and be damaged.

Windings

If current transformers are connected in parallel, they will superpose and supply a high current.

EDIT:

I suppose you drive the transformer with a voltage source.

By the way, it depends how you connect the transformers:

A - primary side in parallel and two independent loads at the output

B - primary sides in parallel and secondary sides in parallel

Say turns ratio is Np:Ns, then for each transformer you have

Vp/Np=Vs/Ns, Np*Ip=Ns*Is.

IE If Np=N, Ns=1, you have a voltage step down transformer

(Vs=Vp/n, Is=N*Ip)

A: You will impose the same secondary voltage to each load, that is Vs=Vp/N.

Input current is the sum of each output load multiplied by transformer turns ratio. If the two transformers have M and N turns ratio, you have Iin = M Is1 + N Is2 (Is1=Is2 only if loads are identical)

This architecture is used in modular / redundant systems.

B: Theoretically, it's like having a single transformer. In practice, I have never seen it. What you do is to split the current in two different cores, so that your losses will be lower for each core. That *could be handy if you wanna use ferrites which are undersized for your application and you don't want to buy a new one.

you can use switching devices and get almost as good results as a motor generator set

It is designed to transfer electric supply from one source to another. It would break the initial connection before making the new connection by manually switching a mechanism from one position to another.

Synchronous motors have no slip. This is because the rotor runs at the same speed as the speed of the rotating magnetic flux of the stator.

The starting current is high because the motor's rotor winding has very low resistance. It's similar to a transformer with a shorted secondary windings. As the motor accelerates,the back emf increases which resist the flow of current in the rotor winding. Hence,the current drop to the rated full-load value.

A current transformer's secondary must never be open-circuited. If the instrument fed by a CT needs to be removed, then the secondary terminals must be short-circuited first. This is because a large, and potentially-dangerous, secondary voltage will appear across an open-circuited CT. Normally, a set of links is provided at those terminals for this purpose.

power must be gotten thru moving parts to the coil

slip rings, festoons, tinsel

modem

nebonda

Aluminium conductor. XLPE. Nonmagnetic armour, PVC outer sheath

the armature current is brought thru the interpole winding near the brushes

this shifts the electrical null to reduce arcing with heavy loads

there were arrangements with small motors to shift the brush holder rings but the interpole has no moving parts and works under all loading conditions

Because if you apply Kirchhoff's Current Law to the junction between the line current and the two phase currents, the line current is the phasor (vector) sum of two phase currents. For a balanced load (only), this works out to 1.732 x phase current.

improvement of power factor

There is a coil which converts ac/ to d/c in some models. Sometimes the insulation fails and the wires gets shorted. The wires are covered with a very thin layer of shellac to reduce the size of the ballast and increase inductance.

Kirchhoff's Voltage Law is good for most applications in electrical engineering. One limitation is that the law does not apply when there is a fluctuating magnetic field present.

by making hole on opposit side of the disk

Staggering of brushes is nothing but displaying the positive brush sets in one direction and negative brush sets in the other direction. This ensures uniform wearing of commutator segments or surface (and avoids steps like between brush sets).

yes

at any particular instant of time

the non linearity is usually time based

so after the capacitors charge and the tubes warm up you have steady state to do the calcs untill something upsets the balance