Electrical energy meter
- 1. 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
- 2. • A device that measure the amount of electrical
energy consumed by electrically Powered
devices.
What is electrical energy meter?
- 3. 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 .
- 4. 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
- 5. 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.
- 6. 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.
- 8. 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.
- 10. Electromechanical energy meter continue…
Working formula
𝑃 =
3600 ∗ 𝐾ℎ
𝑡
Where 𝑃 = Power in watts
𝐾ℎ = The amount of energy represented by one revolution of the disc
in units of watt-hours per revolution .
𝑡 = time in seconds taken by the disc to complete one revolution,
- 11. Electromechanical energy meter continue…
Example : if one revolution take 16 seconds .
what is the power when kh=8 watt-hrs.?
Time t = 16
Kh = 8 [in units of watt-hours per revolution]
then
𝑃 =
3600 ∗ 𝐾ℎ
𝑡
So power =1800 watts or 1.8Kwh or 1.8 unit energy.
- 13. 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).
- 14. 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 .
- 16. Electronic or Smart energy meter
All of those use various smart embedded System for
different features like GSM, Wi-fi ,Prepaid system etc.