circuit that can drive a AC loaded machine..

[j.v.s.swathi]

hai sir/madam...
I had a circuit which is operated with 12VDC power supply...

But,the problem is...I need This CKT to make periodically ON and OFF the AC machine....

 

[mitz]

Pls check these 2 links.
https://tahmidmc.blogspot.in/2012/11/controlling-ac-load-with-mosfet.html
https://tahmidmc.blogspot.in/2012/12/low-side-mosfet-drive-circuits-and_23.html

 

[tpetar]

hai sir/madam...
I had a circuit which is operated with 12VDC power supply...

But,the problem is...I need This CKT to make periodically ON and OFF the AC machine....

Can you give more details, from thread question I cant see what you need.



Maybe you want to control some AC load with your circuit which works on 12V DC, something like timer for On and Off ?

Do you need real time clock timer or just a timer ?

 

[j.v.s.swathi]

Yes,I need to CONTROL an AC machine....to clear ur doubt...just see this link ( **broken link removed** )
where the specification are given.what u sent link( https://tahmidmc.blogspot.in/2012/11/controlling-ac-load-with-mosfet.html ) is very clear to us..but the thing is...V dont know the values of those components.

V r doing this project for this IIT HYD FEST...

we cleard 3 specification(i.e.,3,4,5)...But 1,2 specifications are not cleared yet....so please clear it out as early as possible.....V have very less time...

CKT should b very simple and operation shoud be very perfect.

 

[tpetar]

Use optocoupler with zero cross detection and triac its safer solution.

Always you can ask Tahmid for description and parts of his circuit.

 

[mitz]

@ Swathi: These values were given by Tahmid.

R1 should be between 1k and 5k. I recommend 1k or 2.2k for R2.

Hope you suceed agent Bond in his mission.

 

[mitz]

@swathi: Hope part of the schematic from the attached file "Capasitor ceiling fan controller" might be of help.
But this uses Triac instead of MOSFET

 

[j.v.s.swathi]

by giving AC supply of 220V..,results in damageing of my circuit.

Bcoz it contains all DIODEs and Transistors(MOSFET).

How much supply should I need to give to ckt..?

 

[mvs sarma]

the dc derived from mains , is not isolated.
thus
it would be an issue to drive direct from micro controller.
Opto isolator can be used where the diode section would be driven from micro.

The output transistor should have separately derived DC from the mains
and that can be stepped down to 12V by some zenor and a high value resistor. this devied auxilary voltage need to be used for driving the FET.

Instead of all these confusions,
the best appears to use Opto coupler like MOC3041
where an auxiliary triac can be driven from the internal triac.
and directly AC can be switched. You don't need bridge and FET

 

[j.v.s.swathi]

can you plz send me any circuit of that

 

[mvs sarma]

**broken link removed**
This is but one example. there can be many ways.