Electrical Engineering

In a transformer with a turns ratio equal to 1, the primary current comprises the reflected secondary current plus the magnetizing current necessary to sustain the "back EMF developed across the mutual inductance coupling the primary winding to the secondary. Therefore the primary current is always greater than the secondary current in a transformer with a turns ratio equal to 1. This should be evident by applying Kirchhoff's Current Law to the central node of the "T-equivalent" model of a transformer.

Electrical wire splicing is the act of removing the outer shell of a wire, exposing the inside and connecting to another wire that is also spliced. This also allows you to add length to wiring.

Electrons move onto the object, giving it a static charge.

Apex ;)

inductor was invented by scientist lenz so it is denoted by l..

The neutral wire is simply a grounded power carrying conductor.

It is different than earth ground, which is a protective ground, that is not intended to carry current, however, earth ground and neutral are connected together at the distribution panel. Nevertheless, they serve different purposes, and may not be interchanged in usage.

The purpose in grounding one of the power carrying conductors is to limit the possible voltage potential that might exist between an ungrounded conductor, such as hot, or phase hot, so as to minimize the potential electrocution hazard that might exist if someone were to come into conduct with a hot conductor.

There is no 'active' power in a purely capacitive load. Active power is the result of the supply voltage multiplied by the in-phase component of the load current. In a purely capacitive load, the load current leads the supply voltage by 90 degrees and, so, there is no in-phase component and, hence, no active power.

In order to determine the output voltage of a transformer, you need to specify the turns ratio between primary and secondary. You did not do that, nor did you provide any other information that could be used to deduce the output, so only a general answer can be given.

The output voltage of each secondary is 10 volts (the input voltage) times the number of turns on the primary divided by the number of turns on the secondary. If, for instance, the ratio was 1:3, then the output would be 30 volts. Since there are two secondary windings, this calculation is performed independently for each secondary.

whats a core balance current transformer?

Core Balance CTs are special CTs used to detect Earth faults & usually used for Restricted Earth Fault Protection.

It is a ring type CT through which the cables carrying current of all the three phases (R,Y & B) are passed through. (In a 3phase 3 wire system)

Under normal operating conditions, summation of current through the three phases shall be equal to zero. In event of a fault, the summation of the current shall no longer remain zero (zero sequence current shall flow during earth fault) & thus the fault can be detected.

Because it is made of pure wire with nothing beyond its length and interaction with its neighboring wires to create resistance

A fault occurs by 2 plates sliding along each other and then breaking.

A hot wire ammeter measures alternating current (AC) by using a thin wire that heats up due to the current flowing through it. The amount of heat generated is proportional to the current's power dissipation, which varies with the square of the current's RMS (root mean square) value. A calibrated scale translates the wire's temperature change into a current reading, allowing the device to accurately measure AC without being affected by its frequency. The design ensures that the ammeter responds to the average power over time, providing a useful measurement for AC circuits.

An induction motor connected to an existing ac supply normally runs at less than the synchronous speed by an amount described as the 'slip' which is proportional to the torque demanded at the shaft.

If the same motor is instead coupled to an engine and driven at a speed higher than the synchronous speed, with negative slip, power then travels back into the ac supply and the motor has become a generator. The amount of power produced depends on the speed.

However a normal induction motor will not behave as a stand-alone ac generator.

For ac power generation synchronous generators are invariably used because it is necessary to set and maintain the frequency of the supply accurately.

The offline UPS is in standby mode. The charger is maintaining the battery, but the inverter stage is not running. Power goes from input to output, bypassing the inverter. In this configuration, the charger and inverter design is less, as the charger is usually in trickle mode and the inverter does not need to run continuously. On power fail, the inverter starts up and takes the load. There is a glitch in output, a few line cycles, but most loads can handle this. The online UPS runs all the time. The charger now runs the inverter, as well as maintaining charge on the battery. The inverter supplies the load. Power goes from input to charger to inverter to output. In this configuration, the charger and inverter design is more, as they need to run continuously. On power fail, there is no glitch, because the inverter is already running and supplying the load. Usually, there is synchronization between the inverter and the line, so that failure of the inverter can initiate fall-back to the line without glitch.

Hopefully it's a fuse.

You use an ohm meter to check for continuty, low ohm reading, on the center pin between the two ends of the cable. You would then check for continuity between the shield, or outside connector. If both of those are good, you should also check between one of the center pins and the shield to ensure their isn't a short on the cable.

It isn't necessarily the case. In the UK electricity distribution system, you have 33/11-kV step-down tranformers (where 11 kV is the secondary side) or 11-kV/400-230-V step-up transformers (where 11 kV is the primary side).

Maglev trains are among the safest rapid transit systems in the world. The speed and distance among Maglev vehicles are automatically controlled by the frequency of the electric power fed to the guideway, thus possible collisions are eliminated.

To produce 60 watts at 120 volts, you need 0.5 amps (Watts = Volts * Amps) At 120volts, a 240ohm resistor would produce 0.5 amps (Amps = Volts / Resistance) A 60 watt bulb will have a resistance of 240 ohms. Note that this is the resistance while the bulb is hot. You might measure a different resistance if you use an ohm meter because the filament is cold.

A three-phase 'unbalanced' system refers to the load, as the supply voltages are unaffected by load. So the phase-angle and, therefore, the power factor of each phase will be different -i.e. there will be three different power factors.

Yes, an 8kVA generator can run a small house. A generator this size should be able to adequately power a one ton air conditioner, 18 cubic foot refrigerator, and other small appliances normally found in a small house.

The main disadvantage of a bridge rectifier is that it needs four diodes, two of which conduct in alternate half-cycles. Because of this the total voltage drop in diodes becomes double of that in case of centre-tap rectifier, losses are increased and rectification efficiency is somewhat reduced. This poses a problem when low voltages are required. Another disadvantage of bridge rectifier is that the load resistor R

Land the supply source have no common point which may be earthed.

Waves in phase add to each other and become stronger.

It's a chemical change. A thin layer of silver on the surface reacts with oxygen in the air - to form silver oxide.

no

capacitor start motor