Prepaid energy meters allow customers to pay for electricity before using it, similar to prepaid mobile phones. With traditional energy meters, a person had to read meters and deliver bills each month, which was time-consuming and error-prone. Prepaid meters address these issues by automatically cutting off power when credit is exhausted, eliminating billing delays and disputes. The prepaid system uses smart cards or tokens to recharge the meter remotely via a microcontroller, LCD display, GSM modem and relays. This makes the process more convenient and efficient compared to traditional billing methods.

1. PREPAID ENERGYMETER-ELECTRICITY
BILLING
BY
M. SAMATHA( 12D21A0231 )
EEE IV YEAR
SRIDEVI WOMEN’S ENGINEERING COLLEGE
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2. TOPICS:
Electricity Billing
Traditional Energy meter
Backlogs in traditional system
New improvements made by prepaid system
Prepaid energy meter system
Working of a prepaid energy meter
Do there exist any problems….?
Conclusion
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3. ELECTRICITY
BILLING
Cost incurred for the consumption of
power.
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4. 4
Electricity billing
• It is the billing of a electricity according to energy consumed.
• It is measured in units using a energy meter which may be a
conventional type or a radical one.
• Generally in India we follow 3 Part Tariff system,
Total charges=fixed cost +semi fixed cost + variable
cost =(a + b*KW +c*KWh )
a is a constant charge made each billing period.
b is the unit charge in Rs per kW of metered maximum
demand in KW during billing period
c is the unit charge for energy in Rs per kWh of energy
consumed

5. TRADITIONAL ENERGYMETER
• Electromechanical meter consists of an aluminum
disc positioned between two electromagnets, one of
whose coil is connected to the load and is the
current coil and the coil of another electromagnet is
connected to the supply voltage.
• The interaction of the fluxes between the two coils
is responsible for providing a torque to the disc,
which starts rotating, with the revolutions
proportional to the load current.
• The counter records the number of revolutions and
displays them, which indicates the energy
consumed.
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6. • Electronic meters consists of current and voltage sensors which sense the amount of
current and voltage consumed and this analog signal is sampled and digitized using ADCs.
• The digital signals are then processed using a DSP or a Microcontroller, which then
displays the amount of energy consumed on a LCD or a LED display.
Even though after replacement of digital
meters has not changed the system.
A person from the electricity department
go to one and every house and reads the
wattage consumed and gives a printed
slip of electricity bill.
It is not even get eneded here, for the
payment consumer has to stand in a line
at the municipal offices for hours.
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7. BACKLOGS IN TRADITIONAL SYSTEM
• Time consuming process.
• Errors introduced at every stage are fond of errors with
electro-mechanical meters, human errors while noting down
the meter reading, and errors while processing the paid bills
and the due bills.
• No control of usage from the consumer’s side.
• It is a headache for the government to collect debts due
electricity usage from every customer.
• Problem of power thefts leading to unbalanced billing
causes loss of economy.
• Even people feel it burden to stand in a queue every month
for the payment of bill.
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8. NEW IMPROVEMENTS MADE BY PREPAID SYSTEM
• Pay before use
• Keep customers on supply
• Recover money owed (debt)
• No need to chase payments
• No further actions such as disconnections
• Load and demand side management
• Show true cost of consumption and money left
• Reduce waste – conserve energy
• No billing errors
• Reduces deployment of manpower for taking meter
readings.
• Cost efficient and can reduce problems associated with
billing like No bill production, No bill distribution.
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9. PREPAID ENERGYMETER SYSTEM
Basically like in a mobile phone recharging, the consumer buys a recharge card and gets some energy
units in return of the balance amount. The balance amount will keep reducing for every unit of energy
consumed and once zero, the power supply would be automatically cut off. The amount deducted for
every unit of energy consumed can be controlled by the distribution unit according to the peak hours.
Uses energy meters
which get recharged
using a card or a
key or a code
bought from the
vendor.
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10. Two types:
1. Using a token code to recharge
2. Using a card reads a barcode to recharge
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11. 11

12. WORKING OF a PREPAID ENERGYMETER
1. User pays for the P unit of electricity and go
for consumption
2. As the consumption increases, units left for
usage decreases that follows the money.
3. When the units left reach to a particular
threshold value, the meter gives a warning
message to the consumer to get recharge
soon.
4. If it exceeds the limit and the balance
money reach zero, the relay circuit triggers
and the power cut at the user.
5. It sends a message to recharge the electricity
balance.
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13. WORKING OF A PREPAID ENERGYMETER
MICRO
CONTROLLER
(AT89S52)
GSM
16X2 LCD DISPLAY
RELAY
ENERGY METER
LOAD
AC TO
DC
CONVE
RTER
5V
230/9
T/F
1-PH
230V
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14. COMPONENTS:
1. Microcontroller
AT89S52/51
2. 16x2 LCD display
3. GSM MODEM
4. Relay
5. LED
6. RESET switch
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15. MICROCONTROLLER
• In this system AT89S52/51
microcontroller is used.
• 256 bytes of internal memory.
• 4.0v to 5.5v operating range.
• 32 programmable I/O lines.
• AT89S52 is a low-power, high performance 8-bit
microcontroller.
• Controller receives the commands from GSM
modem and activates relays as per the command.
• And send the feedback SMS to operator through
GSM modem.
• Controller connects the load to the main supply
by operating relays contacts.
RAM ROM
I/O
Port
Timer
Serial
COM
Port
Microcontroller
CPU
A single chip
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16. Liquid Cristal Display
•Interface with either 4-bit or
8-bit microprocessor.
•16x2 display
•Which displays the amount of
power consumed
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17. GSM MODEM
• GSM means Global system for Mobile
communication.
• GSM transfer the instruction to main circuit
from operator and vice versa.
• The frequency range specified for GSM is
1,850 to 1,990 MHz
• A GSM modem is a specialized type of
modem which accepts a SIM card, and
operates over a subscription to a mobile
operator, just like a mobile phone.
•When a GSM modem is connected to a
computer, this allows the computer to use the
GSM modem to communicate over the mobile
network.
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18. RELAYS
• Relay is an electrical switch that opens and closes under the
control of another electrical circuit.
• The phase of main supply is connected to relays.
• OFF condition relay contacts are in open, under ON condition
contacts are in closed position.
• Means it connects the phase to the load in ON state only .
• Input supply required to operate relay is 8-12v .
• The output phase connected to relay range is 7 amp 250v.
• It gives the sound while contacts are closing and opening.
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19. AUXILARY COMPONENTS
• Led lights are used to know the circuit status ,means power in
the circuit is present or not.
• Reset switch is used for restart the controller tasks from the
beginning when ever it is struck.
• Crystal oscillator is used to generate the proper voltage to
relays in controller.(means generating clock pulses).
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20. DO THERE EXIST ANY PROBLEMS ?
• Above average costs for your electricity;
• The best energy deals on the market aren't available to prepayment
meter customers;
• They can be inconvenient because you have to go out to 'top up' keys
and smartcards;
• If you can't reach a shop to top up your meter your energy can be
switched off;
• Older meters need to have their prices updated manually after price
rises or falls, which can take months. This means you could be left
paying old rates and owing a lump sum or paying too much.
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21. ADVANTAGES :
Advantages of prepayment meters include:
• Helping customers to manage their debt and energy usage
• Preventing large, unexpected bills.
• Power consumption
• Reduction in power thefts
• Economical method to the government to collect bill payment
as it is a prepaid type( i.e. reduces the financial risks)
• Better customer service.
• Improve operational efficiencies
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22. 22

23. CONCLUSION
We can reduce the manual efforts to collect the
readings from the energy meter which is a cost
effective solution.
It is user friendly process where prepaid payment –
“pay before use” works just as a mobile recharge we
do daily, can make use of power in an efficient way.
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24. ANY
QUERIES……?
???
JUST PUT FORWARD
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25. THANK YOU
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