AC-DC Power Supplies And Currents
Power Supplies can be divided into two types for electronic devices, linear and switching power supplies. A switching mode power supply has the same rating as a Linear Power Supply but will be a lot more complex and usually Switching Mode Power Supplies are smaller. A Linear Power Supply is used for high current devices. They tend to be a lot bigger and bulkier than the Switching Mode Power Supply and a lot simpler in design.
Linear Power Supplies powered by AC tend to require the use of a transformer to convert the voltage from the mains outlet to a different voltage, this tends to be converted to a lower voltage. However a Rectifier is needed if it is used to produce DC, In addition a capacitor will be used smoothing the pulsating current from the rectifier. AC Power Frequency's relate the frequency the pulsations occur at (a multiple of 50Hz or 60Hz is a good example).
An unregulated power supply will produce a varying voltage depending on the variations and on the load of the AC Supply Voltage. A Linear Regulator will be used for critical electronics applications, the Linear Regulator will adjust and stabilise the voltage. When a Linear Regulator is used with a DC current it will greatly reduce the noise and ripple in the output of the current. They can also protect the Power Supply from overcurrent due to current limiting.
The AC supply in series with a single resistor and diode form the simplest DC Power Supply Circuit, these are very common in the use of rechargeable flashlights.
AC
AC stands for Alternating Current, in Alternating Current the flow of electric charge reverses direction periodically, for instant an AC Current will move forward the backwards over and over again repeating the cycle of movement.
Electricity that is delivered to Residences and Businesses is in the form of AC Electricity. A 'Sine Wave' is the usual waveform of an AC Circuit; different waveforms can be used in different applications tho such as: Square Waves or Triangular Waves. Another example of an alternating current is electrical wires passing audio and radio signals.
DC
DC stands for Direct Current and this is the unidirectional flow of electric current. Batteries, Solar Cells and Thermocouples are a few examples of sources that produce Direct Current. Semiconductors, Vacuum (Ion or Electron), insulators and wires are examples of conductors that DC (Direct Current) can flow through. Direct Current was formally known as Galvanic Current.
By use of a Rectifier, a Direct Current can be obtained from an Alternating Current. The rectifier contains electromechanical elements that will only allow the current to flow in one direction.
Nearly all electronic Power Supply Systems used Direct Current, it is also the current used to charge batteries. Electrochemical processes and the production of aluminium use very large amounts of direct current power supply, railway propulsion also requires a DC Current.
AC DC Power Supply is a very important source of power in the world we live in and many applications require them.
Daniel Owen writes about AC-DC power Supplies. To know more about AC-DC power Supplies, visit http://www.businessmagnet.co.uk
Article Source: ArticlesBase.com
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The current I, in amperes, flowing thru a particular ac(alternating current) circuit at time t seconds is?
I= 120sin(70pi t - pi/6). What is the period of the current?
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Complex algebra for alternating current circuit analysis?
can someone point me to a website that explains how to use complex algebra to do analysis of alternating current elements and circuits containing those elements
i don't know complex algebra that's why i need a site that explains both simultaneously
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Hi can someone help me with this? I know it is not necessarily R&S, but there is more traffic here............
I was having a coversation via e-mail with a friend and we were talking about hydrogen as the way of the future for our energy needs and I was doing some research and compiled this information.
Is my math correct?
A given weight of Deuterium (H2) also called Heavy Hydrogen, can produce about 4 times as much energy as the same weight of Uranium. Fissioning of 1 pound of (0.45 Kilograms) of Uranium produces as much energy as burning 1,140 short tons (1030 metric tons) or 2,280,000 pounds of coal. A short ton in America = 2000 pounds.
So to help you do the math:
If you have X pounds of Deuterium, it produces 4 times the energy of Uranium which produces as much energy as burning 1,140 short tons of Coal.
That means 1 pound of Deuterium = the same as fissioning 4 pounds of Uranium which = Burning 4,560 Short tons or 9,120,000 pounds of coal.
1 short ton = 20,754,000 BTU's (BTU = British Thermal Units = A BTU is defined as the amount of heat required to raise the temperature of one pound avoirdupois of water by one degree Fahrenheit. 143 BTU is required to melt a pound of ice.)
(1 BTU = 1055 joules)
20,754,000 BTU = 21,869.63 megajoules (Megajoule = 1,000,000 Joules). 1 kilowatt-hour = 3,412 BTU.
1 joule = 1 watt second ( watt second = a unit of electrical energy equal to the work done when a current of one ampere passes through a resistance of one ohm for one second. )
1 ampere = 1 coulomb (6.28 x 1018 electrons) per second.
1 ohm = The unit of measure of electrical resistance. ( One volt will force a current of one ampere through a resistance of one ohm.)
1 volt = the force required to send one ampere of electrical current through a resistance of one ohm. It is analogous to water pressure in pounds per square inch. A unit of electrical pressure measuring the force or push of electricity. Volts x amps=watts. The terms potential, electromotive force (emf), and voltage are often used interchangeably. Also is = to performing one joule of work to move or separate one coulomb (6.25 x 1,018) of electrons. 1 Joule = 1/1055 or 0.000947867 BTU's.
1 watt = one joule per second, 1/746th horsepower. Volts x Amps x PF = Watts. (Note: For AC (AC = Alternate Current) circuits, PF (Power Factor) must be included.) Also = 107 ergs per second. Commonly used to define the rate of electricity consumption of an electric appliance. One watt of power is expended when one ampere of direct current flows through a resistance of one ohm.
Power factor = The ratio between Watts (Active or True power) and Volt-Amperes (Apparent power). The Power Factor has a value somewhere between zero and one. This ratio is generally expressed as a decimal fraction.The distribution utility has to provide equipment that will carry Amps, and if the Power Factor is poor (less than about 0.9), the distribution network is inefficient. A power factor of 1.00 is unity. A device such as a ballast( Ballast = device that controls currents in lamps) that measures 120 volts, 1 amp, and 60 watts has a power factor of 50% (volts x amps = 120 VA, therefore 60 watts/120 VA = 0.5).
1 erg = In terms of the joule, 1 erg equals 0.0000001 joule.
There is much more, but I think this is more than enough for what we want to do.
O.K. if we fuse 1 pound of Deuterium, that will produce 99,848,642.8 Megajoules of energy or 27,735,734.1 Kilowatt-hours.
1 watt-hour is equivalent to 1 watt of power used for 1 hour. This is equivalent to 3,600 joules. So, 1 kilowatt-hour is = to 1000 watts of power used for 1 hour and this is the equivalent of 3,600,000 joules.
Thanks for any help you can give....
and there should be a comma between, "Hi" and "can"...
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RLC alternating current circuit question?
in a series L-R-C circuit, what are the phase angle O and power factor cos O when the resistance is much smaller than the inductive or capacitive reactance and the circuit is operated far from resonance?
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Circuit in alternating current?
Circuit in alternating current?
circuit in alternating current?
what it is the formula for a circuit to : the circuit is in alternating current
the first resistance is of 47 omhs, later has two to zener in series, one in opposite sense of the other and the voltage limitor resistance is of 33 omhs, . please i need the fornula
During the positive half-cycle, the diode of above leads and the one of down this in the zone to zener; therefore the exit is trimmed. The level will be the one of the tension to zener (diode in rupture) more 0' 7 v ((Diode with direct polarization). When this the negative half-cycle, happens on the contrary with which an almost square signal is obtained. Whichever greater it is the sinuidal wave of entrance, more perfect will be the square wave of exit
its polarization is always in inverse
sorry for my english!
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The current I, in amperes, flowing through a particular ac (alternating current) circuit at time t seconds is:
120 sin(70pt- p6)
What is the period of the current?
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Alternating Current circuits Questions, please help me!!!?
An ac generator with a max voltage of 20 volts and a frequency of 60 Hz is connected to a 289-? resistor. What is the rms current through the resistor to the nearest tenth of a milliamp?
the answer is 48.9
what is the maximum power dissipated in the resistor to the nearest hundredth of a watt?
the answer is 1.38
I want to know the formulas and steps for the problems.
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