Sunday, January 29, 2012

How EMF filters can protect your home

Electromagnetic fields, or EMFs, are emitted by all electronic devices. This means that EMFs are in your home, in your office, and even outside! Unfortunately, few people are aware of the dangers of overexposure to EMFs and even fewer know how to prevent it. EMF filters are a great way to keep your home safe and reduce the EMF exposure of your family.

Because information about EMFs can become highly technical, many people don't bother to read up on them, as they don't understand the information they find online. If you are in this camp, don't worry! Below are the answers to some common questions concerning EMFs and EMF filter use.

Electromagnetic Field FAQs

Q.:Why are EMFs dangerous?
A.:EMFs can be harmful because they can interfere with the delicate electrical system of your body. When this happens, a variety of health problems, ranging from trouble sleeping to the development of cancer, can take place. Additionally, people have reported fatigue, stress, irregular sensations in their skin, pains, muscle aches, burning eyes, difficulty thinking, digestive disorders, and infertility.

Q.:How can you reduce the EMFs in your home?
A.:Besides following tips to reduce EMF exposure, such as unplugging appliances when not in use and minimizing time spend on the computer and cell phone, EMF filters have been developed to reduce the amount of exposure you experience in your home. Electricity exists at several different frequencies, and the harmful frequencies are often called Dirty Electricity. EMF filters remove the Dirty Electricity from electrical lines, reducing the risk that you will be affected by it.

Q.:Do you need EMF filters in your house?
A.:No, however it is wise if you have electrical devices. Electronic devices could be leaking harmful EMFs into your home. Instead of living in fear of EMF exposure, you can use EMF filters to cut down the amount of radiation.

Q.:Do you need more than one EMF filter?
A.:Yes. Normally, 20 EMF filters are used in the average home; however, you can determine if you need more or less based upon the number of electronic devices that you have plugged into your outlets.

Q.:How long will my filters last?
A.:Because EMF filters are not like other commonly used filters, such as those in your car, they do not need to be replaced. Your EMF filters should last quite some time and only need repairs or replacement if they are damaged.

EMF Filter Expectations

Most people who use EMF filters report that they feel much better after the Dirty Electricity has been cleaned from their home. When using EMF filters, it is important for you to understand exactly what to expect. You will need to buy around 20 filters for them to be effective. Additionally, the filters may spark when you first plug them in. However, they should not make noise and should not have to be replaced unless they are somehow broken (i.e., stepped on).

The benefits of having EMF filters in your home are great, as you will be able to live free from the fear of overexposure to EMFs. Your health, sleep, and overall wellbeing may improve with the use of these filters. It is recommended that you consult with professionals before installing your EMF filters to ensure that you are using the right product in the right places. Once your filters start working, you may quickly notice the improvement!


With Electrical Stimulation to the Spinal Cord, Paralyzed Man Walks Again

Electrical impulses sent to a paralyzed man’s spinal cord allow him to walk again, researchers say. Rob Summers, 25, can voluntarily move his feet and hips and walk on a treadmill with support , in what could be a major breakthrough for the treatment of paralysis.
The research team, led by Dr. Susan Harkema of the University of Louisville, Ky., stressed that the treatment is not a cure for paralysis and that it worked with just one patient in one trial. But researchers not involved in the study say it is promising — one UK doctor told the BBC it was “mind-blowing.”
The findings appear to show that the legs and spinal cord, not the brain, are in control of movement. That means interruption of messages from the brain may not preclude paralyzed patients from walking again — they would just need new electrical signals to stimulate the spinal cord.

Summers appeared in various media outlets Friday to discuss the research.
Weeks after winning the College World Series with Oregon State University in 2006, Summers was hit by a drunk driver, suffering spinal cord damage that paralyzed him from the chest down. Neuroscientists implanted 16 electrodes in his spine, and sent electrical impulses to his lower spinal cord, mimicking the signals normally sent by the brain to initiate movement. Summers was suspended over a treadmill while the signals were transmitted to his spine. Writing in the British medical journal The Lancet , researchers say the spinal cord’s own neural network, combined with sensory information from his legs, is able to to control muscle and joint movement.
Summers trained for two years with a treadmill and physical therapists moving his legs to help him stand and walk.
V. Reggie Edgerton of the David Geffen School of Medicine at UCLA said sensory information is sent via neural networks in the legs directly to the spinal cord. The sensory feedback allows Summers to balance himself, bear his own weight and take steps over various speeds and directions, Edgerton said in a news release .
In a statement, Summers said the treatment has changed his life.
“For someone who for four years was unable to even move a toe, to have the freedom and ability to stand on my own is the most amazing feeling,” he said.
He was left with some sensation below the chest, so it’s not clear whether the treatment would work for spinal cord injury patients who experience no sensation. What’s more, Summers was an athlete in excellent physical condition before his injury, which could have helped his rehabilitation.
Still, his doctors hope that someday, patients with spinal cord injuries could use a portable electrical stimulation unit to move independently once again.
The work was funded by the National Institutes of Health and the Christopher & Dana Reeve Foundation.

The Strongest Electrical Current in the Universe Spotted, 2 Billion Light Years From Here

Galaxy 3C303, Keeping Current Generated from a Very Large Array image, this image shows the huge jet of current stretching for 150,000 light years across galaxy 3C303. Philipp P. Kronberg, Richard V.E. Lovelace, Giovanni Lapenta, Stirling A. Colgate via arXiv
Looking for a source of renewable electricity? Researchers at the University of Toronto have found some serious current emanating from a huge cosmic jet 2 billion light years from Earth. At 1018 amps, the current is the strongest current ever seen, equalling something like a trillion bolts of lightning.
The awesome current was found around the galaxy 3C303, whose core is the origin of a massive matter jet. While measuring the alignment of radio waves around 3C303, the researchers noticed a swift and sudden shift in the alignment of those radio waves, the telltale sign of an electrical current.
Why exactly this is happening is unclear, but the researchers speculate that the black hole at the galaxy’s heart plays a role, its magnetic fields generating this current that is so strong that it lights up the matter jet and helps to drive it outward. Way outward. The jet reaches out some 150,000 light years into interstellar space--farther than the estimated diameter of the Milky Way.

Sunday, January 15, 2012

What Does a Electrical Engineer Do?

An electrical engineer has many potential job functions but most work on designing products that are powered by or produce electricity. Sometimes, an electrical engineer will dedicate his or her time to a single electrical product. While there are millions of potential products an electrical engineer may work on, some examples include medical technology, cellular phones, handheld gaming systems, and airline navigation systems.

When beginning a project, an electrical engineer usually starts by figuring out the purpose of the product. He or she will then plan the circuitry and wiring of the electronic components. A prototype is generally built on which extensive tests are conducted in order to make sure the plans work as designed, and that all of the components work well together. An electrical engineer might also test broken products in order to find out where they went wrong and how the design can be altered to prevent its recurrence. He or she might be responsible for examining existing products that have no known or significant problems simply to uncover whether they can be improved.

Often working in a group with other engineers, an electrical engineer must be proficient in the use of a wide array of engineering and design software and a variety of laboratory equipment. He or she must also be able to provide detailed instructions for the manufacture and use of the final product. The engineer is often responsible for overseeing the installation of the product to ensure it is installed properly and safely.

In order to become an electrical engineer, one must have a thorough knowledge of engineering and technological concepts. He or she must be experienced in the use of computers and electronics, as well as have a strong background in mathematics, physics, design, production, and processing. The effective electrical engineer must also be able to troubleshoot problems, be effective at adapting to new situations as they arise, think critically about potential solutions to problems, and show great attention to detail.

In the United States, a bachelor's degree is usually the minimum education required for entering this field, but many electrical engineers also have master's or doctoral degrees. These degrees are typically in the fields of engineering, applied science, technology, science, or engineering management. Either degree must be accompanied by professional certification prior to practicing as an electrical engineer in the United States or Canada.

Electrical Formulas

The most common used electrical formulas - Ohms Law and combinations

Common electrical units used in formulas and equations are:

Volt - unit of electrical potential or motive force - potential is required to send one ampere of current through one ohm of resistance
Ohm - unit of resistance - one ohm is the resistance offered to the passage of one ampere when impelled by one volt
Ampere - units of current - one ampere is the current which one volt can send through a resistance of one ohm
Watt - unit of electrical energy or power - one watt is the product of one ampere and one volt - one ampere of current flowing under the force of one volt gives one watt of energy
Volt Ampere - product of volts and amperes as shown by a voltmeter and ammeter - in direct current systems the volt ampere is the same as watts or the energy delivered - in alternating current systems - the volts and amperes may or may not be 100% synchronous - when synchronous the volt amperes equals the watts on a wattmeter - when not synchronous volt amperes exceed watts - reactive power
Kilovolt Ampere - one kilovolt ampere - KVA - is equal to 1,000 volt amperes
Power Factor - ratio of watts to volt amperes
Electric Power Formulas
W = E I (1a)

W = R I2 (1b)

W = E2/ R (1c)

where

W = power (Watts)

E = voltage (Volts)

I = current (Amperes)

R = resistance (Ohms)

Electric Current Formulas
I = E / R (2a)

I = W / E (2b)

I = (W / R)1/2 (2c)

Electric Resistance Formulas
R = E / I (3a)

R = E2/ W (3b)

R = W / I2 (3c)

Electrical Potential Formulas - Ohms Law
Ohms law can be expressed as:

E = R I (4a)

E = W / I (4b)

E = (W R)1/2 (4c)

Example - Ohm's law
A 12 volt battery supplies power to a resistance of 18 ohms.

I = (12 Volts) / (18 ohms)

= 0.67 Ampere

Electrical Motor Formulas
Electrical Motor Efficiency
μ = 746 Php / Winput (5)

where

μ = efficiency

Php = output horsepower (hp)

Winput = input electrical power (Watts)

or alternatively

μ = 746 Php / (1.732 E I PF) (5b)

Electrical Motor - Power
W3-phase = (E I PF 1.732) / 1,000 (6)

where

W3-phase = electrical power 3-phase motor (kW)

PF = power factor electrical motor

Electrical Motor - Amps
I3-phase = (746 Php) / (1.732 E μ PF) (7)

where

I3-phase = electrical current 3-phase motor (Amps)

PF = power factor electrical motor

BASIC ELECTRICAL ENGINEERING FORMULA RESOURCES PDF AND DOWNLOAD LINKS

BASIC ELECTRICAL ENGINEERING FORMULA TUTORIALS
Links on Basic Electrical Engineering Formulas

Electronics is an engineering discipline that involves the design and analysis of electronic circuits. Originally, this subject was referred to as radio engineering. An electronic circuit is a collection of components through which electrical current can flow or which use electromagnetic fields in their operation.

The electronic circuit design and analysis rests primarily on two Kirchoff's laws in conjunction with Ohm's law modified for AC circuits and power relationships. There are also a number of network theorems and methods (such as Thevenin, Norton, Superposition, Y-Delta transform) that are consequences of these three laws.

In order to simplify calculations in AC circuits, sinusoidal voltage and current are usually represented as complex-valued functions called phasors. Practical circuit design and analysis also requires a comprehensive understanding of semiconductor devices, integrated circuits and magnetics. Read more...



I = current(amps.), V = voltage(volts), R = resistance(ohms), P = power(watts)
CURRENT:
I = V/R or I = P/V
VOLTAGE:
V= P/I or V = IR
POWER:
I2R or VI
RESISTANCE:
R = V/I
ALTERNATING CURRENT(AC):
Il = line current(amps.), Ip = phase current(amps.), Vp = phase voltage(volts), Vl = line voltage(volts), Z = impedance(ohms), P = power(watts), f = power factor(angle), VA = volt ampers

CURRENT(single phase):
I = P/(Vp cos(f) Read more...


Common electrical units used in formulas and equations are:

Volt - unit of electrical potential or motive force - potential is required to send one ampere of current through one ohm of resistance
Ohm - unit of resistance - one ohm is the resistance offered to the passage of one ampere when impelled by one volt
Ampere - units of current - one ampere is the current which one volt can send through a resistance of one ohm
Watt - unit of electrical energy or power - one watt is the product of one ampere and one volt - one ampere of current flowing under the force of one volt gives one watt of energy
Volt Ampere - product of volts and amperes as shown by a voltmeter and ammeter - in direct current systems the volt ampere is the same as watts or the energy delivered - in alternating current systems - the volts and amperes may or may not be 100% synchronous - when synchronous the volt amperes equals the watts on a wattmeter - when not synchronous volt amperes exceed watts - reactive power
Kilovolt Ampere - one kilovolt ampere - KVA - is equal to 1,000 volt amperes
Power Factor - ratio of watts to volt amperes
Electric Power Formulas
W = E I (1a)

W = R I2 (1b)

W = E2/ R (1c)

where

W = power (Watts)

E = voltage (Volts)

I = current (Amperes)

R = resistance (Ohms)

Electric Current Formulas
I = E / R (2a)

I = W / E (2b)

I = (W / R)1/2 (2c)

Electric Resistance Formulas
R = E / I (3a)

R = E2/ W (3b)

R = W / I2 (3c)

Electrical Potential Formulas - Ohms Law
Ohms law can be expressed as:

E = R I (4a)

E = W / I (4b)

E = (W R)1/2 (4c)

Example - Ohm's law
A 12 volt battery supplies power to a resistance of 18 ohms.

I = (12 Volts) / (18 ohms)

= 0.67 Ampere

Electrical Motor Formulas
Electrical Motor Efficiency

μ = 746 Php / Winput (5)

where

μ = efficiency

Php = output horsepower (hp)

Winput = input electrical power (Watts)

or alternatively

μ = 746 Php / (1.732 E I PF) (5b)

Electrical Motor - Power

W3-phase = (E I PF 1.732) / 1,000 (6)

where

W3-phase = electrical power 3-phase motor (kW)

PF = power factor electrical motor