control circuit design

[future]

hi all..i need to design a circuitthat can control a 45 mins process..any one willing to hear more and assist

 

[shrtrnd]

We used to use programmable logic controllers for that.
What are you using for control? (Or is this a stand-alone configuration?)

 

[future]

ok

thanx shrtnrd...programmable logic controller will be way to advanced....i have in mind simplest control circuit not for industrial application but for gadget appliccation

 

[Electrobrains]

Ok, give some more information.

List input and output parameters, your supply voltage etc.
How do you want to control (from where comes your reference value)?

What do you mean with "45 mins process"? Is it for instance an oven that should keep a set temperature for 45 minutes?

 

[future]

In those lines yes...220vac supply
1.need to maintain temperature constantly for 45 mins via element as well as simultaneously run a small motor that will be used to agitate a paste as thick as dough...
picture this in a unit as small as a micro oven

 

[Electrobrains]

Would you set the temperature with a potentiometer?
If the temperature tolerance is not critical, you could build a simple P-regulator with a couple of op-amps and a dimmer output.

 

[future]

temperature tolerance is not critical both potentiometer as well as building p-regulator can work