i want to vedio automatic phase changer in vedio explain
prakram rajwar
email-prakramraj143[at]gmail.com
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automatic phase changer videos download
This project is developed for the users to change the phase when one or two phase not available.The main part of the circuit is a microcontroller PIC16F73. The three phases are directly connected with three step down transformers and the output of the three transformers are regulated to 5V DC.The three five volts are given as input to the ADC of the microcontroller. The output of the microcontroller is connected with a relay through driver.
The three phase motor is connected with the relay. The display indicates the phases which are currently activated.The microcontroller program is written in such a way that when three inputs are present, the microcontroller sends signal to the driver section and there by operates the relay.If any one or two of the inputs are absent, the microcontroller will not send signal through the output port and thereby it automatically trips the available phase through the particular relay.The microcontroller program is written in assembly language.In three-phase applications, if low voltage is available in any one or two phases, and you want your equipment to work on normal voltage,this circuit will solve your problem. However, a proper-rating fuse needs to be used in the input lines (R, Y and B) of each phase. The circuit provides correct voltage in the same power supply lines through relays from the other phase where correct voltage is available.Using it you can operate all your equipment even when correct voltage is available on a single phase
The mains power supply phase R is stepped down by transformer X1 to deliver 12V, 300 mA, which is rectified by diode D1 and filtered by capacitor C1 to produce the operating voltage for the operational amplifier (IC1). The voltage at inverting pin 2 of operational amplifier IC1 is taken from the voltage divider circuit of resistor R1 and preset resistor VR1. VR1 is used to set the reference voltage according to the requirement. The reference voltage at non-inverting pin 3 is fixed to5.1V through zener diode ZD1. As soon as phase-R voltage goes below 200V, the voltage at inverting pin 2 of IC1 goes below reference voltage of 5.1V, and its output goes low. As a result, transistor T1 conducts and relay RL1 energises and load L1 is disconnected from phase ‘R’ and connected to phase ‘Y’ through relay RL2.