Are there any common timers that are programmable to the second? (my sprinkler timer is programmable only to the minute)

We are using a sprinkler timer to automate the opening and closing of a ball valve by linear actuator. The problem is the sprinkler timer is only programmable to the minute, so it opens, lets water flow for a minute, and then closes. This wastes water as we only need to empy the tank for 10-ish seconds. Any timers that are programmable to the second?

Build yourself a little monostable circuit with a 555 timer - when you power the device, the output goes high for 10 seconds, then it goes off, then the power goes off 50 seconds later and the 555 resets.
paulpaulpaulpaul (author)  steveastrouk8 years ago
Hey, thanks for the answer!

My input voltage off the sprinkler timer is 24v AC. Will the 555 timer work ? or do I have to rectify it to DC?

You can see the actual relays in the project box in the final step of this instructable:


gmxx8 years ago
if you are good with wiring a relay.. the iobridge: http://www.iobridge.com is programmable to the second. it will also tell you the ambient light, tempature, show messages on an lcd display, and let you control servos... all over the internet...