Confused, homework question

In class we have to program an Allen Bradley SLC 500 to do something simple. It can be anything simple. Such as a pretend 4 story elevator or a pretend traffic light. Any suggestions on this, or any books I could read that will be helpful. I never even heard of a PLC before this.
You can e-mail me at [email protected]

Thanks

At this site. Click on downloads then click on Allen Bradley, scroll down until you see elevator or traffic light.
Merry X-Mas

YOu are a student - do not try calculus before you get multiplication down pat. Dont try hurdles until you have mastered walking.

YOu need to start with discrete inputs (switches) and outputs (lights relays) before moving on to more complicated stuff (seqquencers, PID move instructions etc etc)

I think a 4 story elevator is a little complicated for you at this stage -- two floor yes - maybe.

Another good example is a home laundry washer. YOu have it right there and can easily figure out the cycles. A bit complicated for beginner - there are too many cycles.

SO
do a home dryer. All you have to do is turn on teh motor, turn on the heater and have a door switch that stops the motor. Write down the sequence of what happens then transfer that sequence to your program. I left out a couple things in my sequence in previouls sentance - but I sometimes forget to turn things off (that was a hint). The objective is to set up a simple project that you can easily "see" waht is going on and not too complicated and inter involved.

Dan Bentler

I would recommend that you start with a two motor controller.

Start motor #1 when the start button is pressed. After motor #1 has run for five seconds, start a second motor. Pressing a stop button will stop both motors. This will give you a good basic start on simple bit logic and a timer. Then you can build up from there.

The first rung will look something like this (adjust the addresses as well as the logic on the stop button to account for whether you are using a normally closed button (as shown and recommended in real industry) or a normally open button (which may actually be the case in your PLC lab setup)

    STOP        START          MOTOR

    I:0/0       I:0/1          O:0/0

----] [-----+----] [----+-------( )---

            |           |

            |   O:0/0   |

            +----] [----+

Take it from there and try adding a timer to start a second motor five seconds after the first motor starts.

Go to the home page of this site and view the tutorial. Do take a look at the downloads section to see how things might be done, but don't just copy the applications. Play around a bit and see what you can do on your own. It can be a lot of fun to see your own creation come to life so don't deprive yourself of the opportunity.

And please do come back and let us know how its going. If you put forth some effort to learn you will find lots of people here willing to mentor you.

As Alaric said, start with a basic start/stop latch. Then try two motors and use a timer to delay the starting of the second motor. You could also use a timer to sound an alarm for 5 seconds before the motors start. Then just keep adding bits and challenging yourself to write more and more complicated code.

You will find after a while of bashing away at the keyboard when you look back at your project it looks exactly the same as those daunting projects you first saw and thought you'd never understand...

Oh.. and as Alaric said, the first rung will look something like the one he posted...

Good luck ;-)

How about an airport luggage carousel? When the start button is pressed, first a stand clear alarm sounds for a few seconds. Then the luggage carousel starts, then two seconds later the lift conveyor starts. After five minutes, the carousel stops automatically. Include a stop button to stop the carousel early.

Alarics two ideas are good ones two. Basically same as dryer - get two things to run and stop. IF you can get a motor and a relay it is more fun to see the motor run (at least I think so). Also as Alaric said you may as well start to do things as done in the real world.

I forgot to metnion look at the turtorial at this site it is very good for beginner. After that drop the $40 for Melrose book - I used it is good.

Dan Bentler

I like the airport carousel idea. Where a bell sounds for 5 seconds and then it starts. Dan, I ordered Melrose book. I never heard of a plc before this class, so I am going to need all the help I can get.
I have no idea how to start. Anymore helpful hints or ideas please keep them comming because we also have do the code and write a paper.
Thanks everyone!

The downloads on this site, what to use to open them?

For *.RSS you need RSLogix 500

For *. Rsl you need LogixPro simulator ( Download it at http://www.thelearningpit.com/)

HKW53 said:

In class we have to program an Allen Bradley SLC 500 to do something simple. I never even heard of a PLC before this.

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I just have to know...

What is the name of this class

Where is it being taught

What text book is beng used

What is the purpose of the class

What is the teachers credentials (mickey ears?)

If it is not a plc class, how did plcs get included

If it is a plc class, WTF!

curious minds need to know

Those who are not curious, should know also


I think the luggage carosel is an excellant idea. Refreshing, in fact. I would like to see it with a 4 unit stack light to indicated staus, along with an alarm horn (WITH reset button) to tell everyone what is going on.

Good it is nice and simple. Get the thing (motor) to start first. After that add the 5 sec warning timer. Make that interlock to the motor circuit such that motor starts after 5 sec. After that you can add an emergency stop.

Melrose book is good.
There is another book out there by Petrucelli (spelling?) good book but kinda pricy at this stage.

Don't forget to read the PLC manual - and don't let the manual confuse you - some are not written very well and are dang near impossible for a novice - like I was 9 months ago.

Now lessee 12 x 15 was ??

Dan

HKW53 said:

In class we have to program an Allen Bradley SLC 500 to do something simple. It can be anything simple. Such as a pretend 4 story elevator or a pretend traffic light. Any suggestions on this, or any books I could read that will be helpful. I never even heard of a PLC before this.
You can e-mail me at [email protected]

Thanks

Click to expand...

Mickey posted a link to download LogixPro. I highly recommend this program. It has a plc simulator and some automation simulations built in so you won't have to have a plc at home.

I am a bit concerned about your teacher giving such a vague assignment on somthing so new to the class.

HKW53 said:

In class we have to program an Allen Bradley SLC 500 to do something simple. It can be anything simple. Such as a pretend 4 story elevator or a pretend traffic light. Any suggestions on this, or any books I could read that will be helpful. I never even heard of a PLC before this.
You can e-mail me at [email protected]

Thanks

Click to expand...

You kidding right? Who's your so called *teacher*?

In all fairness to the teacher...

In class we have to program an Allen Bradley SLC 500 to do something simple.

Click to expand...

Most, probably all, college level courses give you a syllabus when classes start. This syllabus shows what will be studied and accomplished by the end of the course. Using the above statement containg the term "WE" I will assume that the class or teams from the class have to develop a project at some point in the schedule, it is unlikely that it is due at the start of the class....unless he managed to get into an advanced course without taking the pre-requisite course. A 4 story elevator is not a simple beginner project.

The ONE unusual aspect of this is that it was late November when it was posted, if its a regular college/university semester then he should have been attending class since August (at least first of Sept) so by now should have some idea and training pertaining to the subject.