26-03-2012, 03:40 PM
PREPAID ENERGY METER WITH TARIFF INDICATOR
PREPAID ENERGY METER WITH TARIFF INDICATOR.doc (Size: 1.32 MB / Downloads: 215)
INTRODUCTION
1.1 OVERVIEW
A scheme of Electricity billing system called “PREPAID ENERGY METER WITH TARIFF INDICATOR” can facilitate in improved cash flow management in energy utilities and can reduces problem associated with billing consumer living in isolated area and reduces deployment of manpower for taking meter readings. Every consumer can buy a memory card (is nothing but an EEPROM IC) with a password stored inside it using a MC program. The memory card is available at various ranges (ie. Rs 50, Rs 100, Rs 200 etc…).In our project we have given the name for memory card as smart card. When the consumer insert a smart card into the card reader which is connected in “prepaid energy meter with tariff indicator” kit. Then the card reader will read the stored information and delete the information from the EEPROM IC (smart card) using the MC program. So that the smart card cannot be reused by others. Suppose if a consumer buys a card for Rs.50/- he / she can insert this amount through the card reader so that prepaid energy meter with tariff indicator kit will be activated. According to the power consumption the amount will be reduced. When the amount is over, the relay wills automatically shutdown the whole system. In our project we also have a provision to give an alarm sound to consumer before the whole amount is reduced.
Why Prepayment – Energy Supplier?
• Pay before use
• Keep customers on supply
• Recover money owed (debt)
• Lower Overheads
• No bill production
• No bill distribution
• No need to chase payments
• No further actions such as disconnections
1.3 Why Prepayment – The Customer?
• No Bills
• No hidden surprises
• No having to find the money
• No billing errors
• No socially unacceptable
• Disconnections
3.1 Circuit Description
There are mainly two types of circuits:
3.1.1 Card programmer:
Card programmer is based on AT 89c2051 controller. it recharges the card to Rs.50,100,150,200,250 etc…by using the 4*3 matrix keypad we can get the card programmed
Card is simply an AT24C02 EEPROM chip. it is a 2-wire Serial Interface chip.
How to program a new card?
For making a unit price card for Rs 2.50
1.Insert the card into the Programmer
Dial 1*0250#
The format is
1 for unit price
for start process
0 Higher digit of the unit price
2 lower digot of the unit price
5 Higher digit of the unit paise
0 lower digot of the unit paise
DATA SHEET OF ULN2003:
HIGH VOLTAGE AND HIGH CURRENT DARLINGTON TRANSISTOR ARRAY
A5.1 DESCRIPTION:
The ULN2003 is a monolithic high voltage and high current Darlington transistor arrays. It consists of seven NPN darlington pairs that features high-voltage outputs with common-cathode clamp diode for switching inductive loads. The collector-current rating of a single darlington pair is 500mA. The darlington pairs may be parrlleled for higher current capability. Applications include relay drivers,hammer drivers, lampdrivers,display drivers(LED gas discharge),line drivers, and logic buffers.