Prepayment meters

Prepayment meter and magnetic stripe tokens, from a rented accommodation in the UK. The button labeled A displays information and statistics such as current tariff and remaining credit. The button labeled B activates a small amount of emergency credit should the customer run out.
Prepayment meter and magnetic stripe tokens, from a rented accommodation in the UK. The button labeled A displays information and statistics such as current tariff and remaining credit. The button labeled B activates a small amount of emergency credit should the customer run out.

The standard business model of electricity retailing involves the electricity company billing the customer for the amount of energy used in the previous month or quarter. In some countries, if the retailer believes that the customer may not pay the bill, a prepayment meter may be installed. This requires the customer to make advance payment before electricity can be used. If the available credit is exhausted then the supply of electricity is cut off by a relay. Download high resolution version (1164x522, 72 KB) Electricity prepayment meter, and prepayment tokens. ... Download high resolution version (1164x522, 72 KB) Electricity prepayment meter, and prepayment tokens. ... Marcus Boltonas (Mark Boltan) Marcus Boltonas Brief history The magnetic stripe which is often reffered to as the Bolton is derived from the Marcus Boltonas from the Jurassic period. ... Automotive style miniature relay A relay is an electrical switch that opens and closes under the control of another electrical circuit. ...


In the UK, mechanical prepayment meters used to be common in rented accommodation. Disadvantages of these included the need for regular visits to remove cash, and risk of theft of the cash in the meter. For other uses, see Cash (disambiguation). ...


Modern solid-state electricity meters, in conjunction with smart card technology, have removed these disadvantages and such meters are commonly used for customers considered to be a poor credit risk. In the UK, one system is the PayPoint network, where rechargeable tokens (Quantum cards for natural gas, or plastic "keys" for electricity) can be loaded with whatever money the customer has available. Smart card used for health insurance in France. ... Credit risk is the risk of loss due to a debtors non-payment of a loan or other line of credit (either the principal or interest (coupon) or both). ... PayPoint is a broad term which can be used for different places where somebody can pay for numerous services. ...
Prepayment key
Prepayment key

A similar system, with 2 way communication smart cards, has been used for more than 1 million meters by Elektromed in Turkey. Image File history File links Metadata Size of this preview: 800 × 309 pixelsFull resolution (1668 × 644 pixel, file size: 109 KB, MIME type: image/jpeg) Electricity key meter - the user charges up the key in a shop and the money transfers to the meter. ... Image File history File links Metadata Size of this preview: 800 × 309 pixelsFull resolution (1668 × 644 pixel, file size: 109 KB, MIME type: image/jpeg) Electricity key meter - the user charges up the key in a shop and the money transfers to the meter. ...


In South Africa prepaid meters are recharged by entering a unique, encoded twenty digit number using a keypad. This makes the tokens, essentially a slip of paper, very cheap to produce.


Around the world, experiments are going on, especially in developing countries, to test pre-payment systems. In some cases, a lack of social acceptance has led to non-implementation of this technology.


There are various groups, such as the Standard Transfer Specification (STS) association, which promote common standards for prepayment metering systems across manufacturers. STS is a three-letter abbreviation with multiple meanings, including: Société de transport de Sherbrooke Space Transportation System, the official name for the United States Space Shuttle program sequence-tagged site, in genomics Silver thriosulphate or Silver thriosulfate, in chemistry Scanning tunneling spectroscopy Satanas, a Filipino-American gang Science...


Time of use metering

Time of Usage (TOU) metering involves dividing the day, month and year into tariff slots and with higher rates at peak load periods and low tariff rates at off-peak load periods. While this can be used to automatically control usage on the part of the customer (resulting in automatic load control), it is often simply the customers responsibility to control his own usage, or pay accordingly (voluntary load control). This also allows the utilities to plan their transmission infrastructure appropriately. A public utility is a company that maintains the infrastructure for a public service. ...


Power export metering
Many electricity customers are installing their own electricity generating equipment, whether for reasons of economy, redundancy or environmental reasons. When a customer is generating more electricity than required for his own use, the surplus may be exported back to the power grid. Net metering is a electricity policy for consumers who own, generally small, renewable energy facilities, such as wind or solar power, or uses vehicle-to-grid systems. ... Look up redundancy in Wiktionary, the free dictionary. ... Green energy is a term used by some environmentalists to describe what they deem to be environmentally friendly sources of power. ... Surplus means the quantity left over, after conducting an activity; the quantity which has not been used up, and can refer to: budget surplus, the opposite of a budget deficit economic surplus Surplus product or surplus value in Marxian economics physical surplus in the economic theory of Piero Sraffa Operating... Transmission towers Transmission lines in Lund, Sweden Electric power transmission, or more accurately Electrical energy transmission, is the second process in the delivery of electricity to consumers. ...


This exported energy may be accounted for in the simplest case by the meter running backwards during periods of net export, thus reducing the customer's recorded energy usage by the amount exported. Unless equipped with a detent or equivalent, a standard meter will accurately record power flow in each direction by simply running backwards when power is exported. Such meters are no longer legal in the UK but instead a meter capable of separately measuring imported and exported energy is required. Suppliers offer different rates for imported and exported electricity while meters that go backwards provides a different area of risk for the industry. Net metering is a electricity policy for consumers who own, generally small, renewable energy facilities, such as wind or solar power, or uses vehicle-to-grid systems. ...


In common use are renewable sources (e.g., wind turbines, photovoltaic cells), or gas or steam turbines, which are often applied in cogeneration systems. Another potential upload source that has been proposed is plug-in hybrid car batteries (vehicle-to-grid power systems). This requires a "smart grid," which includes meters that measure electricity via remote control and give customers timing and pricing options. Vehicle-to-grid systems could be installed at workplace parking lots and garages and at park and rides and could help drivers charge their batteries at home at night when off-peak power prices are cheaper, and receive bill crediting for selling excess electricity back to the grid during high-demand hours. This article is about the machine for converting the kinetic energy in the wind into mechanical energy. ... A solar cell, a form of photovoltaic cell, is a device that uses the photoelectric effect to generate electricity from light, thus generating solar power (energy). ... For other uses, see Gas (disambiguation). ... A Siemens steam turbine with the case opened. ... For other uses, see CHP. Cogeneration (also combined heat and power, CHP) is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat. ... Vehicle to Grid (V2G) technology is a bi-directional grid interface for gridable vehicles such as Battery Electric Vehicles and Plug-in Hybrid Electric Vehicles. ... A Smart meter generally refers to a type of advanced meter (usually an electrical meter) that identifies consumption in more detail than a conventional meter, and optionally communicates that information via some network back to the local utility for monitoring and billing purposes. ... This article does not cite any references or sources. ... a park-and-ride bus in Oxford Park and ride terminals are public transport stations that allow commuters to drive short distances in their personal automobiles to catch a ride on a bus or railroad system (usually classified as light rail or the heavier commuter rail). ... Energy demand management is also known as demand side management (DSM). ...


Ownership

Due to the deregulation of electricity supply markets in many countries, the company responsible for an electricity meter may not be obvious. Depending on the arrangements in place, the meter may be the property of the electricity distributor, the retailer or for some large users of electricity the meter may belong to the customer. Deregulation is the process by which governments remove, reduce, or simplify restrictions on business and individuals in order to (in theory) encourage the efficient operation of markets. ... 11kV/400V-230V transformer in an older suburb of Wellington, New Zealand Electricity distribution is the penultimate stage in the delivery (before retail) of electricity to end users. ... Electricity retailing is the final process in the delivery of electricity from generation to the consumer. ...


The company responsible for reading the meter may not always be the company which owns it. Meter reading is now sometimes subcontracted and in some areas the same person may read gas, water and electricity meters at the same time. A residential gas meter of the usual diaphragm style A gas meter is used to measure the flow of fuel gases such as natural gas and propane. ... A typical residential water meter A water meter is a device used to measure water usage. ...


Location
Current transformers used as part of metering equipment for three-phase 400 A electricity supply. The fourth neutral wire does not require a current transformer because current cannot flow in this wire without also flowing in one of the three phase wires.
Current transformers used as part of metering equipment for three-phase 400 A electricity supply. The fourth neutral wire does not require a current transformer because current cannot flow in this wire without also flowing in one of the three phase wires.
Commercial power meter
Commercial power meter

The location of an electricity meter varies with each installation. Possible locations include on a power pylon serving the property, in a street-side cabinet or inside the premises adjacent to the consumer unit / distribution board. Electricity companies may prefer external locations as the meter can be read without gaining access to the premises but external meters may be more prone to vandalism. Current transformers used as part of metering equipment for three-phase 400Amp electricity supply. ... Current transformers used as part of metering equipment for three-phase 400Amp electricity supply. ... A CT for operation on a 110 kV grid A current transformer (CT) is a type of instrument transformer designed to provide a current in its secondary winding proportional to the current flowing in its primary. ... Three phase systems have 3 waveforms (usually carrying power) that are 2/3π radians (120 degrees,1/3 of a cycle) offset in time. ... Image File history File linksMetadata Download high-resolution version (3072x2048, 2587 KB) Power meter in the back of a Dunkin Donuts at a Framingham Rest Stop in Massachusetts. ... Image File history File linksMetadata Download high-resolution version (3072x2048, 2587 KB) Power meter in the back of a Dunkin Donuts at a Framingham Rest Stop in Massachusetts. ... For pylons of overhead lines, see Electricity pylon Pylon Noun from Greek πυλώνας gateway tower like structure, usually one of a series, used to support high voltage electricity cables. ... Wylex standard consumer unit fitted with rewirable fuses Modern Hager consumer unit fitted with MCBs and an RCD A consumer unit is a box of fuses or breakers, usually arranged in a single row. ... A fairly standard American circuit breaker panel manufactured by General Electric and using interchangeable circuit breakers A distribution board (known in the United States as a (circuit) breaker panel, panelboard, or load center or for old ones, fuse box) is a mounting enclosure for multiple electrical circuit breakers. ... Vandalism is the conspicuous defacement or destruction of a structure, a symbol or anything else that goes against the will of the owner/governing body. ...


Current transformers permit the meter to be located remotely from the current-carrying conductors. This is common in large installations. For example a substation serving a single large customer may have metering equipment installed in a cabinet, without bringing heavy cables into the cabinet. A 115 kV to 41. ...


Connection

In North America, it is common for smaller electricity meters to plug into a standardised socket. This allows the meter to be replaced without disturbing the wires to the socket. Some sockets may have a bypass while the meter is removed for service. The amount of electricity used without being recorded during this small time is considered insignificant when compared to the inconvenience which might be caused to the customer by cutting off the electricity supply.


In the UK, the supply and load terminals are normally provided in the meter housing itself, at least for smaller meters (up to around 100 A).


Tampering and security
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Meters can be manipulated so as to make them under-register, effectively allowing power use without paying for it. Image File history File links Question_book-3. ...


The enforcement actions enabled by modern anti-tampering meters are inexpensive compared to the revenue losses and public inconveniences they prevent. Power companies may install remote-reporting meters specifically to enable remote detection of tampering, and specifically to discover theft of energy.


When tampering is detected, the normal tactic, legal in most areas, is to switch the subscriber to a "tampering" tariff charged at the meter's maximum designed current. At US$ 0.095/KWh, a standard residential 50 A meter causes a legally collectible charge of about US$ 5,000.00 per month. Meter readers are trained to spot signs of tampering, and with crude mechanical meters, the maximum rate may be charged each billing period until the tamper is removed, or the service is disconnected.


A common method of tampering is to attach magnets to the outside of the meter. These act in addition to the braking magnets already installed in the meter, causing the meter to under-register. Rectified DC loads will not cause the meter to under-register the amount of power used to a significant degree, nor will a combination of capacitive and inductive load. An electricity meter registers real power (watts), not apparent power (VA); changing the reactive load has no effect on the meter. Similarly, a meter will not run backwards unless you are generating power and feeding it back on the grid from your house (and if detent equipped, will not run backward even then). This is called "net metering", and is commonly used where homeowners have photovoltaic or wind energy systems installed.


The owner of the meter normally secures the meter against tampering. Revenue meters mechanism and connections are sealed. Meters may also measure VAR-hours (the reflected load), neutral and DC currents (elevated by most electrical tampering), ambient magnetic fields, etc. Even simple mechanical meters can have mechanical flags that are dropped by magnetic tampering or large DC currents.


Newer computerized meters usually have counter-measures against tampering. AMR (Automated Meter Reading) meters often have sensors that can report opening of the meter cover, magnetic anomalies, extra clock setting, glued buttons, reversed or switched phases etc. These features are normally present in computerized meters.


Some fraud perpetrators bypass the meter, wholly or in part. This normally causes an increase in neutral current at the meter, which is detected and billed at normal rates by standard tamper-resistant meters.[citation needed] However, most residential meters in use in the United States are single-phase 240 volt meters that are coupled only to the energized lines with the neutral bypassing the meter entirely. This common setup is unable to detect neutral currents.


Even if the meter's neutral connector is completely disconnected, and the building's neutral is grounded to the phantom loop, causing an unsafe house or building, metering at the substation can alert the operator to tampering. Substations, interties and transformers normally have a high-accuracy meter for the area served. Power companies normally investigate discrepancies between the total billed and the total generated, in order to find and fix power distribution problems. These investigations are an effective method of discovering tampering. A phantom loop is an electrical network that uses part of the natural environment to complete a circuit. ...


In North America power thefts are often connected with indoor marijuana grow operations. Narcotics detectives associate abnormally high power usage with the lighting such operations require. Indoor marijuana growers aware of this are particularly motivated to steal electricity simply to conceal their usage of it. A grow-op is a short term for a marijuana grow operation in which cannabis plants are grown in a (usually domestic) setting, sometimes with the intent of creating large amounts of marijuana for commercial purposes. ...


The introduction of advanced meters in residential areas has produced additional privacy issues that may affect even ordinary customers. These meters are often capable of recording energy usage very frequently, usually once every 15 minutes or hour. In an IEEE research paper published in 1989, it was shown that readings of this sort can reveal information about the electrical loads being used within the home. A more detailed and recent analysis of this issue was performed by the Illinois Security Lab, as discussed on the Attested Metering project website. Automatic meter reading, or AMR, is the technology of automatically collecting data from water meter or energy metering devices (water, gas, electric) and transferring that data to a central database for billing and/or analyzing. ... The Illinois Security Lab is a research laboratory at the University of Illinois Urbana-Champaign established in 2004 to support research and education in computer and network security. ...