A motor can be a simple induction machine that rotates with the connection of a simple AC voltage. In applications that require more precise control of speed, torque, or positioning, it is more common to use a 3-phase motor. In order to control this type of motor, signals must be generated that cause the motor to spin properly, using feedback to close the loop and regulate the desired parameters.
Modern solid-state electronic energy meters (also knows as kilowatt-hour meters, etc.) employ recently developed electronic components to measure electrical energy. Basic electronic meters are not just more cost-effective than mechanical meters, but offer further benefits: measurement accuracy of the electronic meter is about an order of magnitude better than that of a mechanical meter, while power consumption is lower by about two orders of magnitude. The electronic energy meter is also better protected against tampering than its mechanical predecessor, and units for prepaid operation (e.g., card readers) and remote meter reading (e.g., wireless, telephone line, or internet) can easily be included.
Lighting ballasts control the starting and operating voltages of electrical gas discharge lamps, also known as compact fluorescent lamps (CFL). Because they do not have an intrinsic feedback mechanism that limits operating current like the positive temperature coefficient of resistance of the filaments of incandescent light bulbs, gas discharge lamps need a ballast to limit electric current. Modern electronic lighting ballasts use solid-state circuitry to transform the voltage and alter the frequency of the supplied power. This eliminates any flickering of the CFL and regulates power more efficiently than is possible with standard magnetic lighting ballasts.
Lighting ballasts control the starting and operating voltages of electrical gas discharge lamps, also known as compact fluorescent lamps (CFL). Because they do not have an intrinsic feedback mechanism that limits operating current like the positive temperature coefficient of resistance of the filaments of incandescent light bulbs, gas discharge lamps need a ballast to limit electric current. Modern electronic lighting ballasts use solid-state circuitry to transform the voltage and alter the frequency of the supplied power. This eliminates any flickering of the CFL and regulates power more efficiently than is possible with standard magnetic lighting ballasts.
"A payment system is a system used for transferring money. With the advent of computers and electronic communications a large number of alternative electronic payment systems have emerged. These include debit cards, credit cards, electronic funds transfers, direct credits, direct debits, internet banking and e-commerce payment systems. Some payment systems include credit mechanisms, but that is essentially a different aspect of payment. Payment systems are used in lieu of tendering cash in domestic and international transactions and consist of a major service provided by banks and other financial institutions. Payment systems may be physical or electronic and each has their own procedures and protocols. They are securely transmitting informations and transactions to a server for authentication and approval. Examples of payment systems that have become globally available are credit card and automated teller machine networks. Mobile payment or known also as Mobile wallet is an alternative payment method. Instead of paying with cash, cheque or credit cards, a consumer can use a mobile phone to pay for a wide range of services and digital or hard goods."
Photovoltaic (PV) modules are composed of many individual solar cells that are arranged in such a way as to achieve desired voltage and current output. The system needs to be protected against reverse current flow in order to avoid dissipating the harvested energy as heat. To simplify the wiring of the cells, bypass diodes must be placed in proximity to the panel in the “junction box” that is typically made of plastic and mounted on the rear side of the panel, and thus exposed to rather high temperatures with limited heat dissipation capabilities. Schottky diodes are well suited and widely adopted for this application because of low conduction losses. The preferred package is axial, but new designs are going to SMD parts. Crystalline PV Modules use the junction box to connect the PV solar cells as strings to the inverter system. The bypass diodes are integrated into the junction box parallel to the strings in order to optimize the generated power of the PV module, even when part of the module is not working due to shadow effects, and to protect the non-working cells against overheating and hot spots. Newer trends involve separating the junction box and the bypass diodes and integrating the diodes into the PV module. Thin Film PV Modules require so-called ""blocking diodes"" between the PV module connectors that should withstand the maximum ""system voltage"" of the PV equipment, which can reach 1000 V. For improved efficiency, some designs use Schottky bypass diodes not only for the strings as in the crystalline concept, but also use several bypass diodes integrated into the module for a group of PV solar cells. Concentrator PV Modules are built with high concentrating lenses that project solar light onto a small solar cell that is mounted on a ceramic substrate. The application requires high-current Schottky bypass diodes and sometimes require ""bare dies"" for direct mounting on the ceramic substrate.
An Uniterruptible Power Supply, or UPS, is required when the AC power that runs sensitive equipment is not reliable or not well regulated or filtered. During power brownouts or blackouts the UPS can provide AC power to the equipment, such as computers or emergency lighting, for a period of time, usually until normal power source is restored. Most UPS circuits include some or all of the system blocks shown above.
