hi..... i made a controlling circuit using PIC18F452. the circuit takes 2 temperature sensing through thermocouples.it displays the temperature on 16x2 LCD and operates 3 relays of 6V DC which further operate 3 AC Relays of 220V AC accordingly!
i have attached the PCB Diagram with thread.
my problem is that when my circuit turns the any of the 3 relays, it do either of the following things:
1) it restarts.
or
2) it hangs.
or
3) it continues operating but shows garbage things on LCD .
or
4) sometimes it works perfectly fine for an hour or a day and then hangs!
i m finding the problem for 20 days but failing.
i also used WDT which removed the problem number 2 of hangs but problem 1 and problem 3 are still there.
some electronics friends of mine suggest that its because of the AC part of Circuit which my Microcontroller is Operating.
plz help.
the circuit in image has 2 parts. 1 used to operate relays and the other part is connected with microcontroller to display and take input of interrupts and turn circuit off!
i have attached the PCB Diagram with thread.
my problem is that when my circuit turns the any of the 3 relays, it do either of the following things:
1) it restarts.
or
2) it hangs.
or
3) it continues operating but shows garbage things on LCD .
or
4) sometimes it works perfectly fine for an hour or a day and then hangs!
i m finding the problem for 20 days but failing.
i also used WDT which removed the problem number 2 of hangs but problem 1 and problem 3 are still there.
some electronics friends of mine suggest that its because of the AC part of Circuit which my Microcontroller is Operating.
plz help.
the circuit in image has 2 parts. 1 used to operate relays and the other part is connected with microcontroller to display and take input of interrupts and turn circuit off!
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