sahu
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what's the difference of MCB TYPE C & MCB TYPE B......
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I don't think so!
Three problems:
1. the time constant of the filter is far too long. For a fast response you need to remove the capacitors after the bridge rectifier. I would suggest you even remove the bridge completely and use head to tail diodes, a normal diode in one direction and a 4.7V Zener in the other direction. Ideally you would use a zero crossing detector to tell the PIC to start a quarter cycle delay then read the peak of the AC directly into the ADC. You can set the trip response time by counting how many cycles the high readings last for.
2. You don't show where the power for the PIC or the relay comes from. Be very careful with the curent transformer as both ends of it are above VSS potential so it must not be grounded.
3. The 1N4007 is connected in the wrong place. In series with the transistor base all it does is limit the base current which is not a good idea. It would be better to connect it across the relay coil with the cathode (+) end wired to the relay supply. With out a diode across the relay coil you run the risk of the transistor being damaged as it turns off.
Brian.
I don't think so!
3. The 1N4007 is connected in the wrong place. In series with the transistor base all it does is limit the base current which is not a good idea. It would be better to connect it across the relay coil with the cathode (+) end wired to the relay supply. With out a diode across the relay coil you run the risk of the transistor being damaged as it turns off.
Brian.
like this.