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.

Digital thermometer

Digital thermometer is basic  need today, because of Corona we can't go to hospital more often, so better make use of this device to check if we have Fever.  During this pandemic Digital thermometer has become basic need.

How does it work

Digital thermometer contain a  small computing system  and a resistor. A change in temperature causes the sensor to notice a change in resistance.  The computer converts the difference in resistance into a difference in temperature and offers a digital readout in degrees.

The thermoresistor sensor is called a Thermistor.

Measurement Conversion

A digital thermistor thermometer provides an excitation voltage or current to the thermistor.

The excitation is converted to a voltage signal by the thermistor and the thermometer then converts the measured voltage to temperature. 

Range of Thermometer Display.

32°–42°C 

(89.6°–107.6°F).

Infrared thermometer

we can find infrared thermometer everywhere nowadays,  without checking temperature we are not allowed anywhere .

Malls, hospitals, office , due to pandemic they make use of this infrared thermometer as safety measure to check the fever.In this device also we can find interesting electronics concept .

Mechanism of thermometer

An infrared thermometer is a sensor that consists of a lens to focus the infrared energy on to a detector,energy is converted to an electrical signal that can be displayed in units of temperature.

Its used to  measure the temperature of a surface from a distance ranging from a few inches to few feet.

Infrared light works like visible light it can be focused on the surface,the surface absorbs the infrared radiation and turns into heat .  heat is turned into electricity .The electricity is sent to a detector,which uses it to decide the temperature of the  surface where IR is pointed.

Infrared Thermometer 

Future of thermometer.

 wearable fever armband.

Wearable device that can check patients temperature continuously ,  when there is increase in fever it can send alarm directly to nurse or care taker.

Remote Car Key

Remote car key is present in everyone hand today,but many of us don't know electronics in it,lets know today.

Remote key means it's a entry system to car without using mechanical key support.Remote key has short-range radio transmitter,which works for certain range which is 5 - 20 meters.when key is pressed it sends coded signal through radio waves to the receiver in the car so that lock or unlock of the car door happens. 

car has sensors to detect fob, for opening of door ,truck and opening of vehicle. 

Few standard frequency.

315 MHz for North America made cars

433.92 MHz for European,Japan,Asian cars.

how to avoid duplicate key is made used in car.

we can make use of Transponder key to find the duplicate key used to ON the ignition.Transponder key have small computer chip inside them,when it's used to on the ignition it will send some code to ignition ,it will respond back if its original key by electronic control unit.this invention happens during world war 2,to find friendly planes on radar.

Rolling code

Remote car key will produce different code in order,Both in Transmitter and Receiver end,So thief cant decode the real code of remote car key,If receiver misses any signal it compares with upcoming 256 codes to match.

The transmitter controller chip has a memory which stores 40 bit code along with function code,when we press Fob 40 bit code is transmitted and receiver decode 40 bit code.

If we don't use rolling code easy to decode the code.

Hacking of system

Using house Wi - Fi ,same frequency device or using Jammer Thief try to hack your system.try to be careful about this.

Microchip

microchip HCS301 one of chip used in remote key.

34 bits not encrypted : 28 bit serial number,4 bits button information, 2 bits status(Repeat and low battery indication)

32 bits encrypted(rolling code),4 bits of button information. 

Few pictures for reference

Car Key

Remote

Future:

If we are far from car also we should know the status of the car,like that remote system will be designed.

For example:

somebody entering the car.

alarm system status.

location of car.

 
   

                                                                                               

Mixer grinder

Mixer is basic need of everyone house,without mixer cooking is impossible today ,It has special attachment to home maker. Without mixer we can't even think of cooking simple dishes.

History of mixer is very interesting 

Hebert Johnson first discovered standing mixer to help in egg mixing and dough mixing.

Mr Mathur designed Indian Mixie which helps in blending Indian Masala. It all started with  dough mixer and scientists taught its difficult to blend Indian Masala in that mixer, so the innovation of mixer came into picture. Scientists love for his wife made him to think mixer grinder to help all home maker. Braun mixer his wife was using and he was asked to repair it, however it was not suitable for Indian masala so he discovered  Indian mixer.

 Mechanism of mixer 

Mixer has universal DC motor,

Which works both in AC and DC current,mixer should run in higher RPM so that it can blend the masala nicely,

universal motor has higher power output with smaller size and starting torque to high and lower speed and to carry high load,means small device running at higher RPM to blend Indian masala.

Small device running at higher RPM  is more interesting here.

750 watt mixer

750 Watt means

Higher Wattage means running at high-speed which helps in blending the Masala neatly.For one minute how fast the blade in the Jar rotate is important.

If we run mixer by 1 hour.

power consumed is calculated by (750watt*1hr)

Energy Transformation in mixer grinder.

The rotation and electricity produces heat energy,this will make blades to rotate and produce noise and small light ,light indicates mixer is connected to electricity switch.

electrical energy is converted into mechanical,heat,noise,light energy.

400 watt mixer

400 watt mixer

Less Watt means

mixer runs at lower RPM,

1 unit of electricity means 1 kw if device is using 400 Watt total power 
total power consumed is 400/1000=0.4 KW

400 KW ,230V

Future :

Universal motor is 70% efficient.

so BL DC motor will be used for more efficient.permanent magnet outside will designed for more efficiency.

Razor

Razor is small device which is present almost everyone house but most of us never taught about how does it work .

Mechanism of Razor.

Simple electronics in that.Razor has small dc motor in that which produces rotary motion which helps rotating disk in razor to rotate and create motion with that oscillating blade help for shave.

DC motor takes electrical energy converts into mechanical rotation energy in shaving machine.

Magnetic field will be produced around DC motor from electrical energy which helps blade to work.

DC motor uses 5-12 V for this particular machine.

DC motor to work continuously we make uses of Battery,battery will be charged with the help of electricity.

Principle:

Razor has adapter for charging , adapter which is connected in home switch at 220 V 

220 V is converted into 5 V in adapter then

Battery gets charged which is present in Razor , battery is connected to DC motor with the help of battery energy DC motor creates motion, this motion helps blade to move according to speed adjusted and do the shaving.

 

Adapter

 

5 V , 1 Amp means

Razor will work at 5 V and 1 Amp, its has resistance

resistance means during shaving, hair which is present on skin it will create resistance according to that we can calculate current used.

Voltage/Resistance=Ampere.

Interesting history.

Gillette everyone would have heard about this  brand,but its name of the person who taught about this invention.

when he told about his idea to scientist and manufactures they denied ,but he didn't give up on his idea .

he was 40 at that age,his taught was converted into safety razor.

from ages we can see shaving set starting it was just a blade.

afterwards for safety razor came into picture.

every device we see can find electronics in that ,how much we are into electronics.

Blade

Blade removing Razor

Few interesting facts about razor.

More than 4000 years back people used to shave.

Before the invention of blade people used few raw materials to shave

Grey rock,Teeth of shark, and clam shells.

Men has 10000 to 30000 hairs in beard.

Clean shave resemble Official look,Wedding function.

Beard men during those they used to pay tax for shaving.

It has become reason to divide classes.

Few pictures

Kemei trimmer 3V ,5W

mzNOVA 

110 V -220 V,3 W

Different trimmer with different voltage and power specifications.

Future 

Nowadays we can find trimmer with different size blade which helps beard styling and look.

Coming days cooling effect while shaving will be included in the machine.

For doing different style different type of blades will be designed.

Motor which uses less power usage and  more efficient will be discovered.

Different size hair clipper.

 

Fm radio

Radio has different emotion in everyone life, FM has become part of everyone life we start our morning by listening to songs from FM, Today i want to share few experience with FM as electronics engineer i was quite curious about working and invention of FM radio

Few facts 

 scientist took almost 20 years to name the word  radio.

 Used in military and marine communication. In 20th century human voice they transmitted in air.

Few people feels its sound waves which is transmitted but its electromagnetic waves which is transmitted in radio.

In that hi fi Fm i wanted to share few details today how it works and what future holds for FM this is Fm which is found in vehicles to listen music,we need to connect to speakers and listen music, speakers need amplifier to boost the voice, home speakers always has inbuilt amplifier.

Manually we can change the channels. Transformers we need to use if we want to decrease the voltage and use it.

As we fix the channels we can listen the music

Future

Now one program  runs in  one frequency

but in future multiple program will run in one frequency.

Mechanism of Radio.

Antenna present outside the vehicle , will attract the magnetic energy of the radio waves and send to FM Receiver.Then signals will be amplified then according to channel tuned we can listen to particular music

Few picture for reference.

Old FM with manual tuning

Nowadays we can see inbuilt FM in mobile for that Fm chips is inbuilt in mobile 

from large size to minute size it has changed.

Upcoming 20 years the availability of radio will changed but it will be part of our life. 

It has more than 100 million subscribers.internet has 170 million subscribers then we can feel the  influence of radio in everyone life