student needing an idea for a sequence

This is my first post on this forum but I have visited this site for about 4 months and have learned a wealth of knowledge. I’m studying DDC control, which is mostly related to the heating and cooling trade. During this holiday break my instructor allowed me to take a PLC home and a few other gadgets. In this class we normally use HVAC controllers but I choose to take home a PLC instead; frankly I find this type of controller much more interesting and user friendly compared to text type programming.

I’m just wondering if you folks could help me find a sequence that would incorporate the resources that I have. First, I’m using an AB MicroLogix 1200 with an analog block that is programmed with RSLOGIX 500 Starter English. Second, I have one temperature sensor that has a range of 50 to 85 degrees F. Plus I have a small frequency drive which I can run a blow dryer or small fan. In addition, I have access to a few more I/O such as light bulbs and toggle switches.

I have experience with control loops but still have trouble with the PID file used with the AB PLC. But I would like to learn to use this file and any other files that would be useful in a sequence that incorporate the inputs and outputs that I have. I would like the sequence to be over 30 or 40 lines of code but obtainable for a student to figure out.

I bet you pros can come up with some cool stuff to do with the resources I have. I’m looking forward toward everybody’s ideas and I have a good idea this will be a fun and great learning experience.


PS. This sequence doesn’t necessarily have to be HVAC based and if anybody can come up with some other type of I/O that can be cheaply purchased, feel free to elaborate.

THANKS FELLAS FOR ALL THE HELP, I CANT WAIT!!!!!!!!!!!!!

I made it by Simatic S7, but as well it can be done by AB, Omron etc.
I try that JPG-image 93 kbytes..

I don't know if this would help or not ... but just this past year a prof and I did research on analog control using the micrologix 1200 with the analog module. We used IR sensors as our input. We were trying to center a can. Anyways, I don't know exactly what it is you are looking for .. I'm still a student myself. I have a powerpoint presentation we did explaining the programming and scaling to parameters for analog control. It might help ya ... as for PID, I'm still working on that myself and I know nothing about hvac. If this sounds useful, send me a pm or email .. I'll send it to ya (that goes for anyone) unfortunately, its too big to post with this message.
jac