Wireless Automatic Meter Reading System for Power Measurement, Load Control and Billing: 

Introduction

Due to use of  improper power management systems, the power requirement is increasing in the development of country’s economy. Over the past years, metering devices have improved a lot, and are expected to become even more advanced, offering more and more services. Meters in the past were electro-mechanical devices with poor accuracy and lack of ability. Recent developments in this direction seem to provide opportunities in implementing energy efficient metering  technologies that are more precise and accurate, error free, etc. The implementation of Wireless Automatic Meter Reading System(WAMRS) provides with many vital features as compared with the analogue utility meter reading with man power.

Working of WAMRS:

WAMRS provides a two way communication between the electricity company and the load by sending in a lot of power parameters and control signal to reach the goal of load management and power demand control. Using WAMRS on distribution automation, can supply many capabilities such as efficient meter-reading, distribution, power monitoring and control, load management and time-of-use rate. With rapid growth of mobile communication network, future application service will gradually concentrate on data transmission service. 

Wireless Automatic Meter Reading System Components:

Energy measuring unit (EMU)

      It consists of a standard calibrated energy meter along with the tampering detection circuit. If any variations other than the rated voltage or specified values are obtained, the ARM -based embedded system (AES) generates the necessary signals required for further operations. In many countries, we have seen that many people try to obtain electrical energy illegally. These incoming losses of stolen power for utility companies are very high. It’s necessary for utility meter to have the capability of tamper detection. 

Relay control unit (RCU) 
 The RCU is a vital part in WAMRS. It provides the useful functionality of remotely switching the power ON/OFF to the user. It consists of a protective relay, breaker control circuit & line breaker.

ARM-based embedded system (AES) 
The AES is termed to the heart of WAMRS. It is designed based on a low power 32 -bit ARM7 LPC2148 processor. AES is a high performance and low cost solution for network applications. It consist of two 10-bit ADCs, with conversion times as low as 2.44 μs per channel, single 10-bit DAC provides variable analog output two 32- bit timers/external event counters and Multiple serial interfaces including two UARTs. The on chip features can significantly reduce the total system cost to design network devices.

Wireless communication module (WCM)

The WAMRS adopts a SIM 300 GSM modem manufactured by SIMCOM limited as the wireless communication module. SIM300 is a Tri-band GSM/GPRS engine that works on frequencies EGSM 900 MHz, DCS 1800 MHz and PCS1900 MHz. The SIM300 is designed with power saving technique, the current consumption to as low as 2.5mA in SLEEP mode.

WAMR Features:

Higher speed.
Improved load profile.
Automatic billing invoice.
Real time energy cost.
Load management.
Alarm warning.
Remote power switches on/off.
Tamper detection.
Bundling with water and gas.