very short intervals

[untamed]

I can see that the trick to this is going to be getting the on/off adjustable to the second. There are lots of timers, but they are limited to on/off by minute.

I control my peristaltic pumps to the second with my Aquatronica...but I'm sure you don't want to go that extreme.

[Delphinus]

Something to look into maybe what they call "repeat cycle" or "percentage cycle" timers.

Some links you can try exploring (look at page 2 of this thread):
http://www.canreef.com/vbulletin/sho...d.php?t=43323&

Happy hunting though .. I don't imagine you'll find these timers at your average hardware store.

[Pescador]

The only programmable timer I can find with a minimum setting of 1 sec is the Mist King timer I use on my viv.
It only has 8 programs so it might not be enough for you.
There are repeat cycle timers that go down to 5 sec and I think I saw some that were min 1 sec. Check out the hydroponic stores.

[spreerider]

there are many electronic timmers that are for industrial and commercial use, just check with an electrical supply store and see what they can get you.
I think Omron makes a fully programable down to the second 24hr timer
i have one at work that can be programed down to the second in a full year period, just needs to be wired up and then programmed

[banditpowdercoat]

Originally Posted by Pescador

The only programmable timer I can find with a minimum setting of 1 sec is the Mist King timer I use on my viv.
It only has 8 programs so it might not be enough for you.
There are repeat cycle timers that go down to 5 sec and I think I saw some that were min 1 sec. Check out the hydroponic stores.

Those are the timers I am talking about. Omron H3scr's have On delay, Off delay, repeat, and other featires built in. BUT, the repeat is the same on/off time. SO, if you set a 5 sec time, it will be 5 sec on/5 sec off. You need 2timers One in ON delay, on in OFF delay.

That price is also a bit high I think. Check eBay for some smokin deals too. Omron makes timers 1/4 the side of that one too. The one in your link is 1/16 DIN Sized. THey make smaller ones, 1/32 DIN I think?

Heres one $20
http://cgi.ebay.com/H3CR-A8-OMRON-Ti...3%3A1|294%3A50



Here is the PDF file on the omron H3CR series timers

http://www.omron247.com/doc/pdfcatal...9H3CRA0302.pdf