TimedelayCircuit

[Electroenthusiast]

I wanted to make a time delay circuit... that which would switch on a 220V Power supply at 6:30PM and switch off at 11:00PM(or 10:30PM), everyday. i'm using IC4060, 14 bit counter... what if i use 4020 ?
Now that i know the circuit will have some error...like
> designed for 24 hrs, but actually it would be 23:50 hrs.(this error causes the circuit large error at long run, like after 7days/10days)
> i'm will be using 2' ic4060(with diff time delay), and when both of them are high, the relay will be ON.

To overcome this problem, i need to auto reset the timer at some time...
How to do it?

 

[mbarazeen]

why do you get 23:50 hrs? you can post your diagram for better explanation.

 

[Mikebits]

This a a case where you should use a micro like a pic.

 

[Electroenthusiast]

This a a case where you should use a micro like a pic.

but cost factor?
' i dont want a very accurate one '... an error upto 10 min is okay for the application
but everyday the time should be in that range(6PM TO 12PM), so i need to use reset

 

[Mikebits]

A simple micro for what you are trying to do cost very little. Cheaper than any other method you may devise.

 

[Transistorman]

you need to use microcontroller for this (if there is no another way )
like PIC12F629 ( i usually use for simple project )

 

[ronv]

Clock

I think this may be what you have in mind. The crystal makes is accurate.

Digital Clock With Timer And Solar Panel Regulator

 

[Electroenthusiast]

hi again,
comparably small error is okay for the circuit...
now i wanted to set the frequency of the timer.
i found the design formula were different from various sources.


I'm using 74HCT4060 instead of CD4060.

Edit: What are the maximum values of R1,R2,C i can have?

 

[Brevor]

Edit: What are the maximum values of R1,R2,C i can have?

YOU should check the data sheet for that information.

 

[Electroenthusiast]

YOU should check the data sheet for that information.

couldn find anything there... will 22M Ohm resistor to a 24 hrs delay at Q14 ?

 

[mbarazeen]

use a crystal osscilator so that you can keep the frequency accurate and constant.

 

[Reloadron]

Every now and then I don't build something when I can get something for a low cost. **broken link removed** are inexpensive, fully programmable in just about anything you could want and frequently have a battery backup to maintain an accurate clock. They are available in just about any country for any mains voltage you could want. Run the output to a relay to handle turning on and off any load you want.

If you build a timer for X hours on and X hours off it is really clueless to what time of day it actually is.

Just My Take
Ron

 

[Electroenthusiast]

ok Reloadron, will have to find that here...

Just to my curiosity:
Anyone knows 'How to set duty cycle in 4060?(/ similar IC's)'

 

[Reloadron]

General Description
The CD4060BC is a 14-stage ripple carry binary counter,
and the CD4040BC is a 12-stage ripple carry binary
counter. The counters are advanced one count on the
negative transition of each clock pulse. The counters are
reset to the zero state by a logical “1” at the reset input
independent of clock.

What do you mean by "set the duty cycle"?

Ron

 

[Electroenthusiast]

What do you mean by "set the duty cycle"?

Ron

Duty Cycle of the Output(any of the bit), the width of High output versus its Time period.

**broken link removed**

 

[Reloadron]

OK, Read this link down to "changing the pulse width. However, you do realize that you will need a few added components.

Ron

 

[Electroenthusiast]

Thanks Reloadron,
I might have to use different IC for that...