Need help designing a controller

Discussion in 'The Projects Forum' started by jjaayy, Apr 22, 2015.

  1. jjaayy

    Thread Starter New Member

    Apr 22, 2015
    Hello everyone ! I was wondering if someone could point me in the right direction to design a controller to control an 120 volt fan. What im trying to do is operate a 120v fan with a controller that controls humidity in a box, say humidity is 85%, than I want to take that humidity to 80% for 24 hours or more or less, than take humidity to 75% for 24 hours, than again take it down to 70% for another 24 hours etc down to about 30% for finish. I have a little electrical knowledge .. I need to make the controller adjustable, maybe I want the humidity to hold at 70% for 2 days instead of 1 day or maybe 1.5 days then turn fan on to bring humidity down to adjusted level than turn off for 24 hours or more or the programmed time. I don't want to use heat to bring down humidity just fan bringing humid air out and drawing fresh air in, yes I know the air outside might not be dry all the time but this is what im trying to start with, without heat.. Any ideas, or can you build this for me?
  2. MaxHeadRoom


    Jul 18, 2013
    You could start with a Honeywell Humidity sensor from Digikey.
    A circuit could be completed with some kind of small microprocessor.