Electrical Energy Meter Presented By: Group 02

Md.Siddikur Rahman Sarker[06]Azharul Islam[07]Md.Majharul Islam[08]Kazi Mahmudul Hasan[11]

Shahjalal University Of Science And Technology,Sylhet-3114

Dept. Of Electrical And Electronic Engineering

• A device that measure the amount of electrical energy consumed by electrically Powered devices.

What is electrical energy meter?

What Is electrical energy?• Electrical energy is the product of power (P) and time (t) of how long

the power is consumed or spend.

W= P*t

Unit of measurement : Kilowatt hour

Kilowatt-hour: The amount of energy consumed by one kilowatt load over the period of one hour .

Types of Energy Meter(EM)

There are two types of EM which works on different mechanism .

Electromechanical induction type meter Electronic meter or solid state meter

Electromechanical energy meter

Measure energy by counting revolution of a rotating disk.

The metal disk is non-magnetic, but electrically conductive.

The number of revolutions is proportional to the energy usage.

Electromechanical energy meter

The disc is acted upon by two sets of coils. one coil produce magnetic flux depends on current and other

depends on voltage which lags by 90 o . That produce eddy current into disk and force to rotate the disk. A permanent magnet exerts an opposing force proportional to

the speed of rotation of the disc. The equilibrium between these two opposing forces results the disc to rotate at a speed proportional to the power usage. The disc drives a register mechanism which counts revolutions.

Electromechanical energy meter continue…

Disk to rotate

1) Voltage coil - many turns of fine wire encased in plastic, connected in parallel with load.

2) Current coil - three turns of thick wire, connected in series with load.

3) Stator - concentrates and confines magnetic field.4) Aluminium rotor disc.5) rotor brake magnets.6) spindle with worm gear.7) display dials.

Electromechanical energy meter continue…

Connection Diagram

Electromechanical energy meter continue…

Working formula

𝑃=3600∗ h𝐾

𝑡

Where = Power in watts = The amount of energy represented by one revolution of the disc

in units of watt-hours per revolution . = time in seconds taken by the disc to complete one revolution,

Electromechanical energy meter continue…

Example : if one revolution take 16 seconds . what is the power when kh=8 watt-hrs.?

Time t = 16Kh = 8 [in units of watt-hours per revolution] then

So power =1800 watts or 1.8Kwh or 1.8 unit energy.

Electronic Energy Meter (EEM)

Electronic Energy Meter (EEM)How it works? Electronic Energy Meter is based on Digital Micro Technology (DMT). Functions are controlled by a specially designed IC called ASIC (Application

Specified Integrated Circuit). Analogue circuits are also present in EEM to “Sample” current and voltage. The ‘Input Data’ (Voltage) is compared with a programmed ‘Reference

Data’ (Voltage) and a ‘Voltage Rate’ is given to the output. This output is then converted into ‘Digital Data’ which is converted into

average value. Average Value / Mean Value is the measuring unit of power. The output of ASIC indicated by the LED as “Pulses”. These pulses are

equal to Average Kilo Watt Hour (kWh / unit).

Electronic energy meter

This type of meter has various features Display in LCD LED monitors Calculate real power, reactive power , apparent power Calculate bill in specified tariff plan . Send billing information to remote wirelessly . Report and record important parameter. Some has prepaid features also .

Electronic or Smart energy meter

Electronic or Smart energy meter

All of those use various smart embedded System for different features like GSM, Wi-fi ,Prepaid system etc.

Electronic or Smart energy meter

Block Diagram of digital energy meter

Block diagram of GPS based energy meter

Thank you