I'm needing a timer that when power is applied, it will close for 15 minutes, then open for 35minutes, then start over, 15 on then 35 off and do this till power is removed.
If what you are controlling is a relatively high amperage, you may want to use a suitably large relay controlled by a much smaller timer unit. As noted, it won't be cheap, even if you spend a few hours on Ebay going thru timers for what you need.