ABSTRACT This project work is on the design and construction of automatic changeover switch. It provides a means of switching from one phase of AC mains to another in the case of failure in the existing phase; it also changeover to generator if there is failure in all the three phases of the AC mains. The circuit also senses the restoration of any or all the three phases of the mains and changeover without any notice of power outage. This project has been improved on the existing types of electromechanical device that has being in use over the years. The aim of this work is to introduce an automatic solution to overcome power fluctuation/phase interruption by selecting next most healthy available phase to feed the equipment without any notice of power outage which is achieved by the use of operational amplifier, timing circuit and high current relay switches and it is powered by 12V dc power supply Hence this has been achieved by the use of operational amplifier, timing circuit and high current relay switches and it is powered by 12V dc power supply.
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Wireless Enabled Automatic Transfer Switch
In recent times, there has been a growing demand in our society on how life can be made much easier and pleasurable and at the same enhances time-saving. With the availability of wireless technology and internet functionalities, the idea of making significant changes from a remote location has now become one of the major devices that give such pleasure. In the global world today, where several complex systems and mechanisms need to be constantly and simultaneously monitored to ensure maximum efficiency, Control Systems have provided a solution that makes it possible. Therefore the main objective of this project is to design an automatic transfer switch with a wireless enabled control device. This automatic transfer switch is good but it can be improved to become more efficient and effective by the introduction of a wireless handheld device that can be used to both monitor and control the entire complex system without having to be resigned to a stationary position.
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Power failure or outage in a country, state or city is highly detrimental to development in public and private industries. The insecurity associated with constant or frequent power failure or outage brings about limitation to power consistent investments, thus hampering the development of industries and multinational ventures. Processes like carrying out surgical operations in hospitals, laboratories which require constant power supply for research, money transactions between banks and more require constant use of uninterrupted power. This research covers the design and construction of a single phase microcontroller-based automatic power changeover. It has the capacity to automatically switch power from national grid to generator and vice versa, once there is power failure in any of the two power supplies. This was achieved by the use of electrical components such as resistors, capacitors, diodes, transistors, opto-isolators etc., integrated circuits that have timing abilities and relays for switching effect. Due to the looping of the pole of the contactor to give 50A current each for PHCN and generator, the maximum power the circuit can withstand on an a.c voltage of 240V is 12KVA. This means the circuit can carry a large amount of power in homes and offices.
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Erratic power supply owing to inability of public power supply utilities to meet the demands of the populace has necessitates the need for an alternative or emergency source of power supply (such as generator set). In this case, transfer switch is usually used to transfer different sources of power to the load. Manual transfer switch involves the use of manpower in operating the generator set and then changing the supply from utility line to generator, when there is power failure, and vice-versa, this often wastes time and sometimes unreliable. Hence, the needs for an automatic transfer switch. The objectives on the design centers on sensing of the primary/main source of power supply when restored, startup the secondary source (generator) when main power fails, shutdown the generator when the main source is power restored as well as automatic transfer of load to the available power source, thereby making the entire process easy and reliable. In order to achieve the objectives, the u.
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