Thanks guys. I love doing this kind of thing. It's going to be even more fun designing a controller from scratch I think.
If you look on ebay, there are a number of PLCs available at fairly reasonable prices... considering what they're worth. The one I used was an old one from work. Served its purpose controlling a water treatment plant for years, and now gets turned into a fish tank controller.
You don't even need anything that amazing to do this. It's not like you're running a paper mill or something that requires millisecond response time.
cinci: I would love to add a touch panel to the outside of my stand. One of the guys at work is working with a tiny 4-5" Magelis panel from Telemecanique. It would be PERFECT! The $2500 price tag is not so cool though... There are actually a few of those PanelView 550's on ebay right now... one that is at $9.99. Do you happen to have a surplus of these?
I'm going to try and get some plexi cut for the front of the box and then I can get it mounted up in the stand.
I'm going to use a couple of these to monitor level in my display and sump. The forks on these things vibrate, so when they are immersed in a liquid, the device senses a dampening in vibratation and turns a contact on. I can use this contact as a condition for the main pump in the logic. If the level in the display gets too high, shut off the main pump and sound alarm/flash light/do something.
