19-01-2016, 04:20 PM
Objective:
Automatic meter reading, or AMR, is the technology of automatically collecting consumption, diagnostic, and status data from water meter or energy metering devices (gas, electric) and transferring that data to a central database for billing, troubleshooting, and analyzing. This technology mainly saves utility providers the expense of periodic trips to each physical location to read a meter. Another advantage is that billing can be based on near real-time consumption rather than on estimates based on past or predicted consumption. This timely information coupled with analysis can help both utility providers and customers’ better control the use and production of electric energy, gas usage, or water consumption.
AMR technologies include handheld, mobile and network technologies based on telephony platforms (wired and wireless), radio frequency (RF), or power line transmission.
INTRODUCTION:
AMR technology is very helpful in the present era because there is a tremendous increase in the use of electricity. Day by day customers are increasing. The basic reason behind this is the industrialization. So it is now necessary that every customer receives electricity bill on time with no mistake in the reading. At present all the manual work is carrying on. So it is not possible to give or generate electricity bill on time. We need more man power to do this. So we have decide to make AMR system by which we can get reading on every customer remotely from the electricity office itself and generate bill on the given time. This will save the important time of the electricity board and user get accurate bill.
Technologies
Touch technology
With touch based AMR, a meter reader carries a handheld computer or data collection device with a wand or probe. The device automatically collects the readings from a meter by touching or placing the read probe in close proximity to a reading coil enclosed in the touchpad. When a button is pressed, the probe sends an interrogate signal to the touch module to collect the meter reading. The software in the device matches the serial number to one in the route database, and saves the meter reading for later download to a billing or data collection computer. Since the meter reader still has to go to the site of the meter, this is sometimes referred to as "on-site" AMR. Another form of contact reader uses a standardized infrared port to transmit data. Protocols are standardized between manufacturers by such documents as ANSI C12.18 or IEC 61107.
Radio Frequency Network
Radio frequency based AMR can take many forms. The more common ones are handheld, mobile, and fixed network. There are both two-way RF systems and one-way RF systems in use that use both licensed and unlicensed RF bands.
In a two-way or "wake up" system, a radio transceiver normally sends a signal to a particular transmitter serial number, telling it to wake up from a resting state and transmit its data. The meter attached transceiver and the reading transceiver both send and receive radio signals and data. In a one-way “bubble-up” or continuous broadcast type system, the transmitter broadcasts readings continuously every few seconds. This means the reading device can be a receiver only, and the meter AMR device a transmitter only. Data goes one way, from the meter AMR transmitter to the meter-reading receiver. There are also hybrid systems that combine one-way and two-way technologies, using one-way communication for reading and two-way communication for programming functions.
RF based meter reading usually eliminates the need for the meter reader to enter the property or home, or to locate and open an underground meter pit. The utility saves money by increased speed of reading, has lower liability from entering private property, and has less chance of missing reads because of being locked out from meter access.
The technology based on RF is not readily accepted everywhere. In several Asian countries, the technology faces a barrier of regulations in place pertaining to use of the radio frequency of any radiated power. For example in India the radio frequency which is generally in ISM band is not free to use even for low power radio of 10 mW. The majority of manufacturers of electricity meters have radio frequency devices in the frequency band of 433/868 MHz for large-scale deployment in European countries. The frequency band of 2.4 GHz can be now used in India for outdoor as well as indoor applications but few manufacturers have shown products within this frequency band. Initiatives in radio frequency AMR in such countries are being taken up with regulators wherever the cost of licensing outweighs the benefits of AMR.
Handheld
In handheld AMR, a meter reader carries a handheld computer with a built-in or attached receiver/transceiver (radio frequency or touch) to collect meter readings from an AMR capable meter. This is sometimes referred to as "walk-by" meter reading since the meter reader walks by the locations where meters are installed as they go through their meter-reading route. Handheld computers may also be used to manually enter readings without the use of AMR technology as an alternate but this will not support exhaustive data that can be accurately read using the meter reading electronically.
Mobile
Mobile or "drive-by" meter reading is where a reading device is installed in a vehicle. The meter reader drives the vehicle while the reading device automatically collects the meter readings. Often for mobile meter reading the reading equipment includes navigational and mapping features provided by GPS and mapping software. With mobile meter reading, the reader does not normally have to read the meters in any particular route order, but just drives the service area until all meters are read. Components often consist of a laptop or proprietary computer, software, RF receiver/transceiver, and external vehicle antennas.
Fixed network
Fixed Network AMR is a method where a network is permanently installed to capture meter readings. This method can consist of a series of antennas, towers, collectors, repeaters, or other permanently installed infrastructure to collect transmissions of meter readings from AMR capable meters and get the data to a central computer without a person in the field to collect it.
There are several types of network topologies in use to get the meter data back to a central computer. A star network is the most common, where a meter transmits its data to a central collector or repeater. Some systems use only collectors which receive and store data for processing. Others also use a repeater which forwards a reading from a more remote area back to a main collector without actually storing it. A repeater may be forwarded by RF signal or sometimes is converted to a wired network such as telephone or IP network to get the data back to a collector.
Some manufacturers are developing mesh networks where meters themselves act as repeaters passing the data to nearby meters until it makes it to a main collector. The Swedish city of Gothenburg is having their electric meters connected in this manner, using the ZigBee protocol. A mesh network may save the infrastructure of many collection points, but is more data intensive on the meters. One issue with mesh networks it that battery operated ones may need more power for the increased frequency of transmitting. It also requires that the meter devices be receivers as well as transmitters potentially making individual transceiver cost higher. However, the additional cost may be outweighed by the savings of multiple collectors and repeater antennas and finding places to mount them.
Some fixed network systems are also capable of being installed as a hybrid AMR system where mobile and fixed network are intermixed by design. In a hybrid system, part of the system is read by fixed network, and parts may read by mobile or other technology, or both. Utilities with low density rural areas may not cost justify the fixed network infrastructure for parts of their service area, using it only for higher density zones or commercial accounts. Some hybrid networks allow reading of a meter by both methods concurrently as a source of redundancy. In the event of a failure of the network due a natural disaster, sabotage, power failure, or other network interruption, the mobile reading system is available in their disaster recovery plan as an alternative means of data collection to the fixed network.
RF technologies commonly used for AMR
• Narrow Band (single fixed radio frequency)
• Spread Spectrum
• Direct-sequence spread spectrum (DSSS)
• Frequency-hopping spread spectrum (FHSS)
There are also meters using AMR with RF technologies such as cellular phone data systems, Zig Bee, Bluetooth, Wavenis and others. Some systems operate with U.S. Federal Communications Commission (FCC) licensed frequencies and others under FCC Part 15 that allows use of unlicensed radio frequencies.
Wi-Fi
WiSmart is an example of a versatile platform that can be attached to a variety of electrical home appliances in order to provide wireless TCP/IP communication over Wi-Fi 802.11 b/g means.
The city of Corpus Christi became one of the first cities in the United States to implement city wide Wi-Fi, which had been free until May 31, 2007, mainly to facilitate AMR after a meter reader was attacked by a dog Today many meters are designed to transmit using Wi-Fi, even if a Wi-Fi network is not available, and they are read using a drive-by local Wi-Fi hand held receiver.
The meters installed in Corpus Christi are not directly Wi-Fi enabled, but rather transmit narrow-band burst telemetry on the 460 MHz band. This narrow-band signal has a much greater range than Wi-Fi, so the number of receivers required for the project are far fewer than the number of Wi-Fi access points covering the same area. These special receiver stations then take in the narrow-band signal and report their data via Wi-Fi.
Most of the automated utility meters installed in the Corpus Christi area are battery powered. Compared to narrow-band burst telemetry, Wi-Fi technology uses far too much power for long-term battery-powered operation.
Power Line Communication
PLC is a method where electronic data is transmitted over power lines back to the substation, then relayed to a central computer in the utility's main office. This would be considered a type of fixed network system—the network being the distribution network which the utility has built and maintains to deliver electric power. Such systems are primarily used for electric meter reading. Some providers have interfaced gas and water meters to feed into a PLC type system.
AMR Hosting
AMR Hosting is a back-office solution, which allows a user to track his/her electricity, water, or gas consumption over the Internet. All data is collected in near real-time, and is stored in a centralized database by high-end data acquisition software. The user can view the data via a secure web application, and can analyze the data using various online analysis tools. The user can easily chart load profiles, analyze tariff components, and verify his/her utility bill. Google Power Meter is an example of this type of web-based tool.
Benefits of advanced metering
Advanced metering systems can provide benefits for utilities, retail providers and customers. Benefits will be recognized by the utilities with increased efficiencies, outage detection, tamper notification and reduced labor cost because of automating reads, connections and disconnects. Retail providers will be able to offer new innovative products in addition to customizing packages for their customers. In addition, with the meter data being readily available, more flexible billing cycles would be available to their customers instead of following the standard utility read cycles. With timely usage information available to the customer, benefits will be seen through opportunities to manage their energy consumption and change from one REP to another with actual meter data. Because of these benefits, many utilities are moving towards implementing some types of AMR solutions.
The benefits of smart metering for the utility
• Accurate meter reading, no more estimates
• Improved billing
• Accurate profile classes and measurement classes, true costs applied
• Improved security and tamper detection for equipment
• Energy management through profile data graphs
• Less financial burden correcting mistakes
• Less accrued expenditure
• Transparency of “cost to read” metering
• Improved procurement power though more accurate data - “de-risking” price
• The benefits of smart metering for the customer
• Improved billing and tacking of usage
Disadvantages of advanced metering
• Loss of privacy - details of use reveal information about user activities
• Greater potential for monitoring by other/unauthorized third parties
• Reduced reliability (more complicated meters, more potential for interference by third parties) Increased security risks from network or remote access
• Meter readers losing their jobs