Electric meter

Electric meter calculate the amount of energy used by revolving dial that turns according to energy consumption. it calculate amount of energy used Kilowatt per hour

meters run by continuously measuring voltage and current to give energy use per hour

For residential purpose its directly connected from source to customer directly from in-line.

For commercial purpose where more than 200 Ampere current is made used they should use current transformer 

Electric meter specification

electric meter 

meter reading for single phase 2 wire class 1

current rating for 5-30 Amps 

energy used in KW h and demand in KW 

standard reference voltage : 240 V

standard frequency :50 Hz

How to check meter reading

meter board calculate energy used per hour =kilowatt/hour

1 kilowatt hour =1000 watt hours.

if we use 50 W bulb for 10 hours energy used is 50 Watts x 10 = 500 Watts(0.5 KW/h)

How to calculate electricity bill from Electric meter

Dial rotating is directly proportional to amount of energy used.number displayed is number of dial is rotated.your meter reading will never reset to zero.

The number displayed represents the kilowatt-hours that has been used since the meter installed. so number will grow every month. 

Current meter reading - meter reading last month report = total kWh used

Total  kWh charge per kWh = Total energy charge

Total energy charge + Fixed monthly fees = Final bill.

How does Electric meter work:

Electric meter has 4 system: Driving system, Moving system, Braking system, Integration system.

The driving system has 2 electromagnets ,upper one is shut electromagnet and lower one is series electromagnet. current is flowing through the wires wounded on electromagnet which produces eddy current.

moving system has disc which will be rotating by eddy current produced by shut and series electromagnet.

braking system used to break the aluminium disc rotation.

Integration method used to record how many times disc rotated means how many kilowatt is used will be recorded and we get the bill.

how does a UPS work

UPS has become basic need for everyone in today's situation, as most of us are working from home.

how does a UPS work

An uninterruptible power supply(UPS)  provides power backup continuously when our regular power source fails or voltage drops to an unacceptable levels

UPS typically used to protect hardware such as computers, data centers, telecommunication equipment or other devices, unexpected power disruption may cause loss in data, to save data UPS was used, nowadays for home purpose also we make use of it.

Parts of UPS 

Rectifier : convert AC (mains supply) to DC (which is stored in battery).

Inverter : convert DC voltage to AC voltage and regulates AC voltage.

Static bypass : Automatically connects load  to main supply if overload or fault occurs.

Battery : power is supplied when mains power fails.

Luminous UPS

1800 watts

It can be connected to any inverter and give battery backup up to 4 to 5 hours during power outrages ,it stores 1800 watts when fully charged.

UPS 

Few facts about UPS

UPS can be small as a notebook or large as a room. The difference in size depends on the requirements. 

Common reason for failures is their batteries.

The first UPS was rotary design, which used a flywheel to give short intervals of backup power.

how does a phone call work

Today whole world is connected, we can call anyone in any part of the world within fraction of time. lets us know electronics behind it.

How does a phone call work

phone is two way radio, consisting of a radio transmitter and a radio receiver. phone converts our voice into an electrical signal , which is then transmitted via radio waves to the nearest cell tower.

cell phones use radio waves to communicate. radio waves carry the information and travel in air at the speed of light. cell phones transmit radio waves in all directions.

Phone

Antenna

cell phones contain at least one radio antenna in order to transmit or receive radio signals. An antenna converts an electric signal to the radio wave.

An antenna is a metallic element for transmitting and receiving specific frequencies of radio waves. older generation phones has ex tractable antennas, modern cell phones has inbuilt antennas. nowadays we have inbuilt Wi -Fi , Bluetooth and GPS.

Optical fiber communication.

To make a call to far distance ( from India to America ) few system is involved back-end. previous days when we used make international calls it would connect with the help international gateway exchanges(switches). nowadays with the help of fiber optics and voice over internet protocol(VoIP) international calls can be dialed without an operator.

Optical fibre is connected between countries through sea bed.

When we diall international number from our phone, our ISP  will route the call to international gateway with the help of routing then other end ISP will connect our call to end user.

Future 

Due to optical fibre laying under sea telecommunications throughout the world has became cheaper.

International calls using internet has become very cheap already.

how does a Door bell work

A doorbell is a signaling device placed near a door to a buildings entrance. doorbell make life much easier. with a simple push of a button ,friends, family member can announce their presence outside the door.

First doorbells were mechanical , nowadays we have electrical doorbells operated by push-button switch.

how does a Door bell works

wired and wireless

wired mechanism  

When switch is pressed , which is present near the door activates a signaling device (bell or buzzer).

when switch is pressed it closes the doorbell circuit. one terminal is connected to transformer . A doorbell transformer steps down the 240 V to (5 to 20) V, another terminal is connected to signalling device which produces voice.

The heart of a doorbell is electromagnet. doorbell uses the magnetic field created by the electromagnet to move a magnetic piston to strike two tone bars.

Wireless mechanism

Doorbell button contains radio transmitter powered by a battery.

when button is pressed radio signal is detected by the receiver, it activates a sound chip and play the music.

Frequencies used is 2.4 GHz ISM band.he

Mechanical bell

Previous days we used to see mechanical bell .

if we pull the rod connected to bell, we can hear the voice.

Future door bell 

Sensors will be made used to sense object in-front of door and activate the signal. It helps in security of the house also, if someone wants to enter home without permission.

Few pictures for reference 

 Door bell

Switch 

Even in simple device like door bell electronics is made used, and made our life easier.

Lighter

Lighter we use everyday many times to ignite the gas burner. But we never taught how it's working,  lets us know today.

Working mechanism

The gas lighter consists of a piezo-electric crystal over which a spring loaded hammer is placed. The hammer and spring set up is attached to button. when button is pressed , the hammer is moved away from the piezo-electric crystal. The spring releases the hammer which hits a crystal of PZT ( Piezoelectric ceramic material ) or Quartz crystal.  

Quartz is piezoelectric,which means it creates a high voltage . due to high voltage air is ionized and acts as a path for the discharge resulting a spark, which when exposed to gas and air mix it produces flame. 

Lighter

what is piezoelectric effect

piezoelectric effect is the ability of some piezoelectric material to generate an electrical charge in feedback to the mechanical stress.

piezoelectric effect is reversible ,which means when we apply mechanical stress to the piezoelectric material we receive some electrical charge on output, and when we apply electricity to the piezoelectric material , then it compress the piezoelectric material.

Piezoelectric application 

Many application we can see using piezoelectric effect like,

• Musical greeting card.
• We can generate electricity by using piezoelectric device placing on stairs,  as humans walks mechanical energy is converted into electrical energy. The energy generated here can be used for charging 40mAh button cell battery for 1 hour .

Piezoelectric effect has many uses in our day-to-day life, like when we workout in gym mechanical energy which is release can be used to convert into electricity .

medical application it's used in ultrasonic Imaging.

Induction stove

Induction stove is generally found in everyone house nowadays, if gas is empty or to cook something immediately we make use of Induction stove.

Induction cooking uses electric current directly to heat vessels through magnetic induction.

 An induction cooker transfers electrical energy by induction from a coil of wire into a metal vessel that must be ferromagnetic.

The coil is mounted under the cooking surface, and a high frequency alternating current is passed through it. The current in the coil creates a dynamic magnetic field.

Interesting facts about Induction stove.

cooking with induction stove save time, A traditional gas stove passes heat to the pan via flames, but an induction cook-top directly passes the heat to the pan.

Induction cooking saves tons of energy, instead of losing heat through flames.

Induction stove mechanism.

Inside each cooking zone, there a tightly wound coil of metal. when you turn on the power, an alternating current flows through the coil and produces an invisible high frequency, alternating magnetic field all around it. 

Place a pan on the cooking zone and the magnetic field produced by the coil penetrates the iron inside it.

The magnetic field induces electrical(eddy) current inside the pan, turning into a heater

Heat from the pan flows directly into the food or water inside it.

Induction stove 

Induction stove consists of

Induction is connected to motherboard

motherboard consists of Filter capacitors and IGBT and Rectifier Diode,

A large copper coil forms the magnetic field.

220v is passed through this device.

Voltage is 230 V and 50 Hz , power :1900 W

 

Microwave oven

Microwave oven is a part of modern kitchen today, it helps to save energy and save time.Beautiful invention has beautiful electronics in it, lets know it 

Microwaves are produced inside the oven by an electron tube called a magnetron. The microwaves are reflected within the metal interior of the oven where they are absorbed by food. Microwaves cause water molecules in food to vibrate, producing heat that cooks the food.

Few interesting facts about microwave 

Microwave oven was found during world war 2 by accident.

microwave energy was used for radar system. Accidentally scientist discovered that microwaves could be used for cooking.while conducting experiments with a new style magnetron, a candy bar in his pocket melted.

The first commercial microwave oven was produced in 1947.The oven was about 6 feet tall and weighed about 750 lbs.

The heart of  the microwave is magnetron, a device which produces radio waves. These waves excite water molecules within food ,causing them to vibrate rapidly. This vibration results in heat, cooking the food from within.

Microwave cooking times are shorter, cooking with a microwave preserve Vitamin C and other nutrients that break down when heated.

Microwave saves energy and saves time.

Microwave Heating principle.

Microwave heating is a multi-physics phenomenon that involves electromagnetic waves and heat transfer ,any material that is exposed to electromagnetic radiation will be heated up.The rapidly varying electric and magnetic fields lead to heating.

Microwave working.

Inside the strong metal box , there is a microwave generator called a magnetron. when we start cooking, the magnetron takes electricity from the power outlet and converts it into high powered  radio waves. Radio waves reaches food compartment through a channel called wave guide.just like light bounces back through wall , microwaves bounces back through wall and penetrate through food and helps in cooking.

MICROWAVE OVEN

A microwave oven consists of 

Transformer to transfer energy to the magnetron

Cavity magnetron which converts high voltage electric energy to microwave radiation

a magnetron control circuit(usually with a microcontroller)

a short wave-guide(to send waves to chamber)

metal cooking chamber

metal wave guide stiring fan

control panel.

READINGS

Commercial frequency used for microwave is 2.45 GHz.