Tuesday 31 May 2016

Best insulator for electricity.

Only having a conductor isn't enough. We need protection so users don't get harm from the conductor. So insulator are used to cover the conductor. This will prevent from getting harm even though the insulator are been touch. So lets look out the best insulator for electricity.

1) PVC ( polyvinyl chloride)


When comes to best insulator for electricity,the first thing comes into your mind is PVC. PVC are now widely used in electrical wiring. Even cables are used PVC as insulator. These cables are insulate by a PVC pipe so the cable will be protect even get fire or chemically damage.Cost for PVC are low and it's light to carry.

2) Ceramic 


Electrical ceramic insulators are used in applications that require a non-conductive rigid component and/or source for heat dissipation. Although all ceramic formulations can be used in electrical applications, Steatite and Alumina (all grades) are the most common choice due to their excellent electrical properties.This ceramic insulation mainly used in high voltage transmission for overhead transmission lines.This high voltage cable will produce heat and these heat will absorb by ceramic.

3) Mica


Mica is unusual in that it is a good electrical insulator at the same time as being a good thermal conductor. This insulator also used in high voltage and low voltage cable and both used in overhead and underground transmission power lines.

4) Quartz 


Quartz crystals act as insulators with their high electrical resistivity.In fact, quartz crystals are able to act as excellent insulators even at elevated temperature. Clear fused quartz is said to oppose electric current better than opaque or translucent types of quartz and rightly have higher values of electrical resistivity.

5) Glass 


Glass is a perfect insulator. It commonly used in underground higg or low voltage cables.
Is resistivity is also very high and has low coefficient of thermal expansion.It has higher tensile strength compared to porcelain insulator.As it is transparent in nature the is not heated up in sunlight as porcelain.The impurities and air bubble can be easily detected inside the glass insulator body because of its transparency.Glass has very long service life as because mechanical and electrical properties of glass do not be affected by ageing.

Monday 30 May 2016

Types Of Wiring : Surface Wiring


Surface wiring are not used today. This kind of wiring are used in village or poor maintenance house. Now days wiring are most used conduit and PVC Pipe to install wiring. Although this wiring old,but it a basic for every wiring system. This wiring is only use single phase current.  So lets look about surface wiring.

This wiring are mount on surface. Means it doesn't need PVC,Conduit,or Conceal wiring. This wire are supported by a saddle.


 It's basically contain three wires. That are Live.Neutral and Earth.

This wiring can make it into 9 angle and T junction.
This type of wiring need too much of work. If any fault happen,it's easy to detect,but it's hard to fix
and have poor mechanical protection,means this wiring can be easy get accident. This wiring cost cheap because it no need much of accessories. It's impossible for three phase wiring because there will be to much wiring and poor protection and easily get accident. If you successful done this surface wiring,
Now you can do the wiring by your own and 
light up your house brightly.  


Sunday 29 May 2016

Effect of Electric Shock

Although electricity give some current to our home and some electrical device,but It does also harm to human and some species like rat,lizard and others. So lets see how electricity give harmful effect on us.



YELLOW BAR

The yellow bar shows, that range 1mA to 30mA aren't harmful to adolescent,but for children is it harmful. This is because if a children is physically weak or sick this will be so critical for them if they had a shock between the range. This also get effect on old age people,if they get any shock between that range,their muscle will cramp or freeze.

ORANGE BAR 

This orange bar are the range that our home are supply current between 50mA-400mA.If children,adolescent or old age people get shock between the range, the will suffer some pain or numbness.

RED BAR  

This range in the red bar is totally dangers. It can cause serious damage to human being. Only trained and competent person can handle this kind of current to do some maintenance. 

Alright folks, now you understand why electricity some times hurt you. Every person in the world knows the feels when the electricity pass through you,because that the true love between a person and electricity. But it will kill you if you touch for long time. So
Keep yourself and other safe and always beware of your home electricity  

Friday 27 May 2016

Van De Graaff Generator

Have you seen 'Mr Bean School Open Day' episode? In that episode he touch the van de graaff generator but unfortunately his hair not get charge. Funny rite. Actually his hair get charge but he comb his hair so much and it's can't get up. So let's see now how Van De Graaff Generator works.

This is a Van De Graaff Generator. It's has several parts. Dome,Column,Belt and Discharge wand.

Dome                  : It's a place that positive charge build there.
Column               : Connects and insulates the base and dome.
Belt                     : Runner Up and Down by driving motor.
Discharge Wand : Produce sparks when bring near to the dome.
Ground Nut        : Transfer electrons to ground connection.
Metal Bar           : Separate charges between belts.

How Van De Graaff  Generator Works  

There's a motor in a base. That motor will run the belt like a conveyor belt. There's a metal bar or ' comb ' are attach to the grounding nut and  in the dome. As the motor  start move the belt will produce electrons in lower roller, the electron will trap at the lower metal bar. Then the positively charge are move up and build positive charge at upper roller and upper metal bar in the dome and Some electrons are there at upper roller. That electrons will goes through the grounding nut. Now the dome is positive charge. The negative charge will be build in Discharge wand. 

When the discharge wand bring close to the dome,it will bring a sparks. The sparks happens depend on the voltage. This generator run in DC ( Direct Current ). So it's not dangerous. Because the current are too small like in Tesla Coil.

Now what!! Just put your hand on the dome and the the current pass through your body and keep smile while your hair rise up. If your hair doesn't rise up,Use wooden chair and stand up on it. This is because the current pass through you body will go to the ground. If you stand up on a wooden chair,the current can't escape and flows through your body.

RISE YOUR HAIR WITH ELECTRICITY

Thursday 26 May 2016

Ohm's Law

In 1827, This dude a German physicist Georg Simon Ohm (1787–1854) found out the relationship between the current I, flowing in a metallic wire and the potential difference across its terminals. He stated that the electric current flowing through a metallic wire is directly proportional to the potential difference V, across its ends provided its temperature remains the same. This is called Ohm’s law.

Ohm's Law state that current ' I ' flowing through a metal conductor is directly proportional to the potential difference ' V ' across the conductor. if temperature is constant.

This graph that current against voltage show when the conductor obey the ohm's law that will be the straight line.The formula for this is :
                                                                           OR


The resistance ' R ' of a conductor define as the ratio of the potential difference for voltage ' V ' across the current ' I ' flowing through it.
 The dotted line show that resistance is stable with constant temperature. So it's mean when the current ' I ' flowing through a conductor ,the potential difference ' V ' also increase. So the formula for this is

Calculation Of Ohm's Law

We have formulas for ohms law now. So it's easy to find out the valve of voltage,current and resistance. So let see some examples. This example is based on the schematic below.
1) If the the current is 6A and the value of resistor is 2Ω. Find the value of voltage ' V '

Steps : Formula V=I x R
                          V= 6 x 2
                                12V

2) If the voltage is 12V and the resistance is  2Ω. Find the value of Current ' I ' 

Steps : Formula I = V/R
                          I = 12/2
                                 6A

3) If the voltage is 12V and the current is 6A. Find the value is resistance  ' R ' 

Steps : Formula R = V/I
                          R = 12/6
                                  2Ω

Easy rite.Don't forget to put symbol for each value. So now you able to understand ohm's law and able to calculate the value of  unit in the circuit. Just you need a circuit and some exercise. 




 

Wednesday 25 May 2016

Best conductor for electricity.

Conductors are nerves for electricity. As usual if a current need to flow it's need conductor. A good conductor gives a good current flow, doesn't mean the conductor is perfect. It has to face some resistance to avoid conductor get heat. So now lets know the best conductor for electricity.

 1) Copper


When comes to good conductor of electricity in your mind, you first thought about conductor. Yes it's a good conductor,but doesn't mean it has no resistance. It has resistance but low. Copper are used i electrical wiring and its has size depends on cable for installation. Copper is heavy,so you need a strong hand to carry and so expensive too.

2) Aluminum 

Aluminum is a good conductor too.but it has high resistance than cooper. Aluminum still use in electrical wiring,but in come cases like reduce cost or temporary wiring. Aluminum so light enough to carry even your hand isn't strong. It's not expensive.

3) Brass


Brass is a mixture of copper and zinc. It is a good enough to conduct electricity. It's so rare in electrical wiring. It has resistance,so it doesn't require to install in wiring.

4) Stainless Steel


Stainless steel is form of steel containing chromium and resistant to tarnishing and rust. It used in making refrigerators,knife and so on. But It also used in electricity but also rare like brass and it resistance is high. Expensive and heavy too.

5) Silver


 When mention about silver,don't be surprise.It's a pure conductor than any other conductor. If sliver is install in your house wiring,OH BOY you are so rich!!!! Silver is so expensive and heavy. People won't buy silver for electrical installation because in electrical wiring and any other installation copper and aluminum are best choice use.

Tuesday 24 May 2016

Electromagnetism : Use of electromagnet.

In this world,electromagnets are everywhere from our own use at home and some heavy duty work at industry. Electromagnet change the world where we live now. No electromagnet means No technology. So now lets see use of electromagnetism.

1) An Electric Bell

 An electric bell consist two electromagnet with wounded solenoids in the opposite direction. When the switch press,a current flows through the solenoids and the electromagnet will energize. This will attract the soft iron armature. When the movement of soft iron armature break the contact,the circuit is off. And the cycles repeat by energizing the solenoids by giving Ding!!! Dong!!! Ding!! Dong!!! sound.

2) Telephone Earpiece
 Inside a telephone earpiece,two electromagnets are fixed with permanent magnet. When the current of varying the magnitude passes through the solenoids,the strength of the electromagnet changes. The diaphragm is pulled by the electromagnets with change the force.Hence the diaphragm vibrates and a sound of similar frequency as received by earpiece.

3) Electromagnet In Industrial Use

 This huge electromagnet are use in cranes to lift heavy and craft metals. This electromagnet can lift ferromagnetic materials like iron,steel,cobalt and Nickel. It's also separate non-ferromagnetic like copper,aluminium and lead. It's work similar to home made electromagnet,but this need huge amount of current to produce huge electromagnetic field.

4) MRI (Magnetic Resonance Imaging) Machine

 Magnetic resonance imaging (MRI) is a test that uses a magnetic field and pulses of radio wave energy to make pictures of organs and structures inside the body.

Monday 23 May 2016

Electrical distribution board of Home and Industry Installation

In electrical distribution each voltage is step down at substation and finally we receive 230V/415V to our home or to industrial areas. So this voltage is flow through the Distribution Board and we able to control the circuit for our own need.

                                     


Home                              Industrial
Distribution                Distribution
board                                    Board






 We see this this kind of board in our home and some industrial areas as the image shown. We describe each of the equipment in the last blog. So now lets see how to wire industrial and domestic distribution board.

1) Domestic Distribution box (Single Phase)
  
In domestic distribution in our home,the wiring is simple (Piece of Cake). Just you need single phase main switch,RCCB and MCB. Now see how the wiring goes as the image shown.

 
Very simple right.But every house loads like fans,lights,sockets are different. So more MCB are needed to wire those loads. So as the wiring above this is image shown the distribution board after wiring.
2) Industrial Distribution Board (Three Phase)

Industrial distribution board are common used in Industrial.But also used in house like double story,bungalow and so on.This is because when the loads are much heavier so single phase current can't power all the loads. So three phase current are used to provide heavier loads like more air-conditioner, Induction stove and so on. So lets see the wiring of industrial distribution box.

You need three phase main switch,RCCb and MCB. As the picture shown,each phase connected through one MCB. Another image shown after wiring installation.
Now you are able to wire single phase and three phase to your home electrical distribution board.


SO YOU ARE A TECHNICIAN FOR YOUR HOME!!!!!!!!!!!!!!

Sunday 22 May 2016

Fault in Electrical circuits

There's no guarantee that every wiring you done isn't perfect. but when you test, something happen to the wiring that might bring fault to your wiring. So lets find out some faults.

1) Open Circuit (Incomplete Circuit)

 After you done some wiring but eventually your wiring doesn't power any lights or fans. That fault is called 'open circuit'. This fault happen when the wiring is loose contact or cable might be disconnect. To fix this,you need to tighten the wire and connect back the wire.


2) Short Circuit ( Hot or Live wire have contact with Neutral wire)
This kind of fault is very common happen in our house. This fault happen when live or hot wire have contact with neutral wire. This fault can be happen maybe your house wiring too old and loose contact or can be interrupt by mechanical interference like rat in your house have bite with your house wiring and end up with rotten mice.

3)Earth Leakage ( When Earth wire contact with Live or Neutral wire)

Earth is so important in electrical wiring that keeps every electrical device and house keeps save. If this earth failed to keep safe, then earth leakage fault happen. this fault happen when earth have contact with live or neutral wire and over current will be produce due to this fault. this over current will be prevent by RCCB (Residual Current Circuit Breaker) that will trip immediately when the current reaches between 30mA-300mA due to type of RCCB.








Friday 20 May 2016

Electromagnetism



While preparing for an evening lecture on 21 April 1820, Hans Christian Orsted made a surprising observation. As he was setting up his materials, he noticed a compass needle deflected away from magnetic north when the electric current from the battery he was using was switched on and off. This deflection convinced him that magnetic fields radiate from all sides of a wire carrying an electric current, just as light and heat do, and that it confirmed a direct relationship between electricity and magnetism. This is where the electromagnetism born.( Source : Wikipedia)

Electromagnet can be easily made by take a long wire and make a coil around the nail. Then connect the both end of wire to positive terminal and negative terminal to the battery. Now you got a electromagnet.

When the current flow through the coil of wire it produce a magnetic field around. The positive terminal will be north pole and negative terminal will be south pole. If the both terminal connect in opposite direction the the negative will be north pole and positive will be south pole.


The magnetic field will be create along the coil will be like in this picture below.
This is not a permanent magnet. The magnetic field will be weaker due to the power loss of the battery. so it's called temporary magnet.

NOW YOU CAN MAKE ONE TEMPORARY MAGNET TO PLAY WITH YOUR
LITTLE CHILDREN


Friday 13 May 2016

Troubleshoot plug and socket problems


When you left your electrical application turn on your socket,but something you heard a noise that actually comes from the socket you turn on. Wait don't panic!!!! It's just a simple problem. Now we are here to solve it. Let's find out the problems and solution.

Problems :

1) Short circuit : If live and neutral wire are accidently have contact. The MCB on your house distribution box will trip.

Solution : Check your socket wire and fix with correct terminals.

Problems

2) Earth fault : If live or neutral have contact with earth. The RCCB in your distribution box will trip and your whole house of electricity will shut down.

Solution : Correct the earth and live or neutral terminal and on back the RCCB

Problems :

3) Fuse blown : Your plug or socket will get melt by sparks. This is because your socket or plug experience over current that can cause by electrical device fault or socket and plug fault.

Solution : Replace a new fuse with correct current rating and new plug or socket. Check the terminal of  plug and socket.


NOW YOU KNOW THAT THE PROBLEMS AND SOLUTION. NO MORE SOCKETS AND PLUGS EXPLODING



Wednesday 11 May 2016

What's inside a Incandescent light

On previous post, we learn about types of light bulb and their connection. Now we going to learn what inside a incandescent light bulb. This is a basic for every light bulb that revolutionize till today.Lets see what inside a Incandescent Light bulb.



 1) Glass bulb : protect the inner components and block infrared or Ultra violet light. It's made from Quatz glass

2) Tungsten filament : This is the filament that produce heat and light. It's has more reisistance because it's thin.

3) Contact Wire : This contact wire that connect to live and neutral that complete one loop to light up the bulb.

4) Stem : Not the plant stem :P It's a glass mold that holds the contact wire and supports wire.

5) Support wire : This will support the tungsten filament. If the filament is not in fixed place or fall off. The bulb will not light up. NO MORE LIGHT BUY NEW BULB :'(

How it's Works
 
When the light bulb is power up the contact wire that hold tungsten filament is heated and produce light. When it's heated and produce light,gas like argon,xenon,krypton are bounce right back toward the filament, where it will rejoin the solid structure. Since inert gases normally don't react with other elements, there is no chance of the elements combining in a combustion reaction.

Tuesday 10 May 2016

Electrical safety and precaution


In electrical,there's many accident cause to trauma,unconscious and even death. So we need safety and precaution to avoid these accident and keep you safe. There's several safety and precaution so Let' look out.

1) Don't turn on Socket or switch by your wet hand.


If you hand wet and you turn on switch or socket, the water in your wet hand will get in to the switch or socket and get electrocute and you will be unconscious. Dry your hand before turn on some electrical device

2) Always ground or earth your electrical device

Your electrical device are earth or ground. This will prevent consumer from getting electric shock. If the earth or ground fails, the consumer will get shock and the electrical device is unsafe to use

3) Don't add some many power point


Your sockets carries certain amount of current. If you add so many plug and other electrical application,the fuse in socket will blow. This will harm to consumer and the house wiring.

4) Insulate or replace damage wires.

Wires are common in damage by natural,mechanical or chemical. If you insulate or replace the wire,your wiring and electrical device will be safe to use. if didn't, it can cause some serious electrical fault.

5) Always get permission from professionals.


If you are learning or pre electrican, whatever electrical project you done,always ask permission from professionals to test the project. If you didn't ask for permission, you at risk from getting accident.

6) Clean your workplace after project or wiring done

After you done some wiring, you should always clean the workplace to make sure everything is secure from prevent happening accident. Most of the accident cause by unclean workplace. Make sure clean it for your and others safety.

7) Keeps your tools after used

Tools are so useful. But sometimes it's bad when you didn't take care well. Keep the tools that you already use. When the tools is all over the place even you are not using it may cause serious injuries to workers and others or even death.