Auto selection of any available phase, in 3 phase supply system

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Auto Selection of any Available Phase, in 3 Phase Supply System


Auto Selection of any Available Phase, in 3 Phase Supply System Introduction  The basic idea for the development of the project is to provide supply to the single phase load if any of the phases, out of the 3 phases misses.  The three transformers are connected to the 3 phases supply. It automatically switch to next phase while one phase is misses.  For monitoring the phase shifting we are using NAND gate logics.  The relay driver IC to change the load to the next phase through the contacts those are fed from all the three phases.  At final condition it works on inverter. http://www.edgefxkits.com/


Auto Selection of any Available Phase, in 3 Phase Supply System Working  Three phase supply are given to three independent transformers connected in together with another transformers from receiving supply, an inverter.  The secondary of the transformers are used to develop DC by half wave rectification and then deriving four number of opto isolators individually.  The DC supply from all the three phases and inverter supply are combined and then fed to the regulator IC 7805 for the circuit operation power.  The relays connected drive the load with interlocking logic from the NO/NC contact such that the 1st phase load automatically changes over to any available phase in the event http://www.edgefxkits.com/


Auto Selection of any Available Phase, in 3 Phase Supply System Description of power supply  The basic idea for the development of the project is to provide supply to the single phase load if any of the phases, out of the 3 phases misses.  The three transformers are connected to the 3 phases supply.  It automatically switch to next phase while one phase is misses.  For monitoring the phase shifting we are using NAND gate logics.  The relay driver IC to change the load to the next phase through the contacts those are fed from all the three phases.  At final condition it works on inverter. http://www.edgefxkits.com/


Auto Selection of any Available Phase, in 3 Phase Supply System

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Auto Selection of any Available Phase, in 3 Phase Supply System Hardware Requirements        

Transformers Logic Gates Resistors Capacitors Relay Driver Relays Lamp Diodes

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Auto Selection of any Available Phase, in 3 Phase Supply System And Gate description  The 4000 Series CMOS range, and contains four independent CMOS AND gates each with two inputs. Pin Description    

Pin 7 is the negative supply Pin 14 is the positive supply Pins 1&2, 5&6, 8&9, 12&13 are gate inputs Pins 3, 4, 10, 11 are gate outputs

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Auto Selection of any Available Phase, in 3 Phase Supply System Relay  A relay is an electrically operated switch.  Current flowing through the coil of the relay creates a magnetic field which attracts a lever and changes the switch contacts.  The coil current can be on or off so relays have two switch positions and have double throw (changeover) switch contacts as shown in the diagram.

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Auto Selection of any Available Phase, in 3 Phase Supply System Resistor

Capacitors

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Auto Selection of any Available Phase, in 3 Phase Supply System Relay driver  The ULN2003 is a monolithic high voltage and high current Darlington transistor arrays.  It consists of seven NPN Darlington pairs that features high-voltage outputs with common-cathode clamp diode for switching inductive loads.  The ULN functions as an inverter.  If the logic at input 1B is high then the output at its corresponding pin 1C will be low. http://www.edgefxkits.com/


Auto Selection of any Available Phase, in 3 Phase Supply System Applications ďƒ˜ In this work, an automatic three phase changer comparator has been designed, built and tested. ďƒ˜ The system operates smoothly as expected. It is reliable, durable and portable. The cost involved in developing it, makes it much more affordable than comparable product.

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Auto Selection of any Available Phase, in 3 Phase Supply System Conclusion ďƒ˜ Further the project can be enhanced by incorporating power semiconductor devices such as thyristors/IGBTs for instantaneous changeover to the next available phase. ďƒ˜ This overcomes the drawback of the changeover time generally witnessed by relay switching operations.

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