Timer circuit help

[paul60]

I am looking for a design for a timer circuit.
This is to switch a water mister on for 30 seconds every 5 minutes
this is to cool solar panels this will run for 5 hours.
water valve operates on 24volts AC 50/60 HZ
If i can purchase this type of timer online please let me know
If not just have to build one
I have a 555 ic
thanks Paul

 

[73's de Edd]

SIR paul60 . . . .

Your locale is not being provided, other than your having " spunky monkeys in your garden" , which might suggest of the tropics, which might relate to your having adequate and frequent rainfall . . . ergo . . .quasi distilled water plus adding additional micro particulate filtering and the capability of free soft water / rainfall storage in a cistern..

Should you, instead, have highly mineralized / hard water . . . . you are going to have massive problems with water delivery and spray mist orifices . . . not to mention the time resultant UGLY effects upon the surfaces of the solar panels.

73's de Edd . . . . .

Now I may not have lost ALL of my marbles, but there’s definitely a hole in the bag…

 

[paul60]

SIR paul60 . . . .

Your locale is not being provided, other than your having " spunky monkeys in your garden" , which might suggest of the tropics, which might relate to your having adequate and frequent rainfall . . . ergo . . .quasi distilled water plus adding additional micro particulate filtering and the capability of free soft water / rainfall storage in a cistern..

Should you, instead, have highly mineralized / hard water . . . . you are going to have massive problems with water delivery and spray mist orifices . . . not to mention the time resultant UGLY effects upon the surfaces of the solar panels.

73's de Edd . . . . .

Now I may not have lost ALL of my marbles, but there’s definitely a hole in the bag…

Make sense. as i live in the caribbean Barbados lots of lime in the water here
was hoping to keep the temperature down to increase the efficiency

 

[AnalogKid]

5 minutes is a loooong time for a R-C timer circuit such as a 555. Better to go with an oscillator/divider or a microcontroller such as a PIC.

If you want to buy rather than build, there are several programmable timers on ebay with a relay output. Does the timer circuit or device have to run on the same 24 Vac as the valves, or is there a separate power source available such as 12 Vdc?

One approach is to use a cheap lamp timer to create the 5-hour operating window every 24 hours, and have that timer control power to the solenoids and power to the timer.

ak

 

[73's de Edd]

I done that timed spraying to my 3 ton refrigerated air conditioning units outside condensing unit, years before it was even being considered, except in commercial situations.
That, along with a sun barrier for that outdoor unit, has done wonders for its longevity- - - shorter run time- - - long time cost savings .

73's de Edd . . . . .

It is just absolutely amazing how many times people in their right minds believe something, that nobody in their right mind would believe.

 

[paul60]

5 minutes is a loooong time for a R-C timer circuit such as a 555. Better to go with an oscillator/divider or a microcontroller such as a PIC.

If you want to buy rather than build, there are several programmable timers on ebay with a relay output. Does the timer circuit or device have to run on the same 24 Vac as the valves, or is there a separate power source available such as 12 Vdc?

One approach is to use a cheap lamp timer to create the 5-hour operating window every 24 hours, and have that timer control power to the solenoids and power to the timer.

ak

no it does not have to run on 24 vac. a separate power source of 12volts can be made available. can you point me to a programmable timer on ebay that might work? thanks Paul

 

[AnalogKid]

I'm almost positive this will do the job, but deciphering the instructions is up to you:
https://www.ebay.com/itm/12V-DC-Mul...h=item3ab6848f46:g:KTQAAOSwLzdWRpo1:rk:1:pf:0

Here is another flavor, analog adjustments but uC based:
https://www.ebay.com/itm/DC5V-12V-2...121a2d3df:m:mBUD2BB0PFi-1EGg8w_NI1A:rk:2:pf:0

ak

 

[paul60]

I'm almost positive this will do the job, but deciphering the instructions is up to you:
https://www.ebay.com/itm/12V-DC-Mul...h=item3ab6848f46:g:KTQAAOSwLzdWRpo1:rk:1:pf:0

Here is another flavor, analog adjustments but uC based:
https://www.ebay.com/itm/DC5V-12V-2...121a2d3df:m:mBUD2BB0PFi-1EGg8w_NI1A:rk:2:pf:0

ak

Hi thanks for the help not sure that i can wrap my old brain around this , but i will give it a go thanks again paul

 

[Bluejets]

Cooling systems are essentially a "built-in" feature i.e. water or cooling agent is normally circulated in an enclosure around the cells, not spray water over the top.
Think any efficiency increase you perceive will be at the cost of reduced output from the build up of minerals on the surface of the glass, water cost and pumping and equipment upkeep costs.

 

[(*steve*)]

You could spray water on the back of the panels. No problem with lime buildup there. However the panels are not likely designed for water to be sprayed onto the back of the panels (as they are for the front).