Survivalism & Self Sufficiency Topics > Homesteading and Self Reliant Living

Learning to use a PLC (Programmable Logic Controller)

(1/4) > >>

Bobo:
So, I've decided that I'm going to learn how to program a PLC. I think it could be really useful for everything from automatic control of a water tank levels, air conditioners, watering systems, rabbit feeders, chicken feeders, heater control systems, electrical power control systems, intruder systems, ect... pretty much anything that I might have to do over and over again, I want to automate.

My format of choice will be the MicroLogix 1000 from allen bradley. The controllers are around 75-250 each, the software is free, and the programming cord is about 50 dollars.

Does anyone have any ladder logic code written which can help me understand how to do this better? Has anyone else done this on their homestead?

reefmarker:
Yikes!  While I agree a PLC can be used to do lots of usefull things, Allen-Bradley and inexpensive are two mutually exclusive things!

I don't know the layout of the MicroLogix but usually the controller is inexpensive compared to everything else you have to drop onto it to make it do something usefull.  Digital ins and outs and analog ins and outs can add many $100's of more expense to the project.  I have been involved as the specifier and end user of lots of PLC's from allen bradley that we use for motion control, and they are very robust, but they are not the worlds most friendly products.  The level of "free" help from AB is really close to zero.

From what you are talking about, you may want to look at the numerous house controllers that are out on the market now.  They are not cheap (well they are compared to AB), but they are made for doing exactly what you want and they are easy to use.

Sorry to be a wet blanket about this.  If you do get into PLCs the hardest thing most people have trouble grasping is everything happens at the exact same time.  The first line of the ladder logic is not executed before the last line it all happens at once, just like if it was a bunch of relays all wired together (which is what is simulating).

Bobo:
Do you have a recommendation on which pre-made house controller is more preferred and why?

JC2:
Ive been watching this thread and wondering how much input you would get. I do find this very interesting because there are alot of things that could be automated. I did buy an automatic door opener (from McMurray) for the chicken coop, and that is but one example of automation to make your life a bit easier. With a basic stamp that could be done for for a lot less than what i paid for it. Of course that takes basic knowledge of programming.
I use to go all out for halloween and started getting into the basic stamp and logic controllers, but it has been awhile. I would suggest visiting a few halloween forum sites and look at their props (automated not static)  section as alot of individual use the automation and can help getting you some basic commands for programming.
Im sure this sounds alittle on the odd side (visiting a hallowreen forum for homesteading ideas), just concentrate on the mechanics behind the prop and see how it wrould apply to what you are doing.
I.E at a haunted house you step on a mat and something jumps out at you - translate that to stepping on a mat or waving your hand in front of a sensor and your gate to the barn opens automatically for you. The cost would be about 30 bucks.
Currently i am overseas but when i get home, adding automation to my farm is something i will do.

Bobo:
Totally a great idea. I'm an electrical engineer, so building basic circuits which work on 24VDC relays is a piece of cake. Most of my parts for circuits I source from www.taydaelectronics.com which has awesome prices, cheap shipping and no tax.

I think as time goes on, I'll start to post what I've done with PLC for the community and hopefully get some good constructive feedback!

Navigation

[0] Message Index

[#] Next page

Go to full version