controlling a smoker oven.

Hi guys.
Can any one figure out what's wrong with this(trying to find a plc thaqt will do the trick)
I don't know programing but if some one can understand the chart I made. I am half way to heavens.
Hanan.
P.s.
I am attaching with jpeg and bmp.
priting the chart shows better.

smoker control

Sorry,
It seems like the chart file is too big.
I was able to up load an .xls version of the chart in the industrial electrical maitenance site. look at identifing i/o.
www.patchn.com/forum.
thanks.

This is the Excel file

You can view it by clicking on this:
Smoker Chart 2

At least I hope this works

Intro to PLC

This LINK might work better.

I've looked at your Powerpoint flow chart, Word flow chart, and Excel sheet.

You're definately getting closer with each attempt, but still a long way off.

I lost you in the Excel when you got to Step 6 - Subroutine 1. But I've got all sorts of questions:

1) Does the Blower Motor EVER go off?
2) You have a START button. Is there a STOP?
3) You refer to the HEATER, SMOKE GENERATOR, and BLOWER MOTOR as N.O. contacts. Do you really mean that the PLC must ENERGIZE its output to them in order to turn them OFF?

Start once more, first focusing on the big picture. No fancy tools, just text. Think about each step that the machine is going through. DON'T TRY TO DESCRIBE IT IN PROGRAMMING LANGUAGE. Just picture it in you mine, and tell us what you see. Your description should have four parts: A step number (just for reference, the steps don't necessarily have to be performed in order), a description of what the step is about, the actions that the PLC must take during the step, and the transition conditions (and the steps that they transition to)

Step: 0
Description: Initial conditions. The operators have hust come to work.
Actions: Everything is OFF
Transitions: When START button is pressed, go to step 1.

Step:
Description:
Actions:
Transitions:

Step: 1
Descr:
Actions:

Step: 1
Description: Get Smoke Generator ready.
Actions: Turn on Heater (PID setpoint = 185ºF). Turn on Blower
Transitions: When Temperature = 185ºF, go to step 2

Step: 2
Description: Smoke Tofu for 10 minutes
Actions: Turn on Smoke. Start 10 minute Timer. Heater PID setpoint = 205ºF
Transitions: When timer is done, go to step 3

Step: 3
Description: ????
Actions: ???
Transitions: ???

Now this is just a big guess based on your spreadsheet. You'll need to fill in the blanks and fix my mistakes.

Once you are done, look at the system from the standpoint of each output and ask yourself two questions:
"What conditions turn the output ON?" and
"What conditions turn the output OFF?"

Once you have done this properly, your code should write itself.

But we can't do it for you. We can't know your process until you have described it completely. And once you've described it, and if you know the basics of PLC programming, you will be able to do it yourself.

Good luck. Feel free to post again with a better explanation.

(In the meantime, consider buying Phil's book. There's a link to it at the top of the page)

intro to plc...

Hi, again.
Allen you are on line now good.
If you like I could give you a call.
You guys are so advanced with computers it's sickening.
I tried yesterday to post the xls. File in this forum and it didn’t work.
Allen.
To your questions: I will buy Phil’s book after I will exhaust reading the dl305 manual I have. However, if that will not help, looks like need to see a Dr.
I just finished reading an article (in Investors business Daily) about 10 point on the road to success it implies: It is better to be out standing in few subjects than be average in many. I was not the best chief engineer S.F ever had –but no one could beat me in troubleshooting.
Regretfully I left the trade 12 years ago to become the best-smoked tofu manufacturer in America. At this point I am not sure my attempt to slide back to the area of my last profession is right. (Although it intrigues me a lot). At any point of our correspondent if you guys see that I am hopeless please give it to me. I will do it hard wiring with lesser quality control of the process.
As for the questions you posted:
In sub routine 6 as dry bulb temp goes down together with wet bulb temp. (Natural condition).
I need to maintain a certain R.H as smoke is inserted (step 5- damper deenrgized).
Up until now the process was depending on temp of the product in the oven.
Step 5 starts 10 min after the product received its 205 f. So far I am good.
The 175 # is an arbitrary could be lower.
Now.
Sub 6: I am setting DRY bulb set point. Let say 100f this should be maintained for the duration of the
Timer setting likes 2 hrs.
–Heater comes on as DRY temp. Goes lower than that.
Dry bulb reached 100.
Heater is on.
Damper deenergized Basically, always, when heater is on pamper deenrgizes unless told differently.
NEW Wet bulb set point (was 175) let say 125F. (The dry temp goes down from 205 f)
Damper is deenrgizes (looking at the new wet b temp.)
Smoke gen. Is on
Blower is cycling
Wet b Set point reached.
Blower cycles, Damper deenrgizes.
Wet b higher than 125 -blower on. Damper energized.
Blower stays on until wet b set point is reached again damper energized.
Wet bulb went back to 125 –blower off (to cycle) damper deenrgizes.
In the dry bulb routine (shall I set a different stage there?) the temp is arbitrary.
There are very important conditions.
Every instance the heater‘s on the blower is on
When heater is on it is preffered to have the damper deenrgizes to kip heat from getting out.
When the damper is energized the smoke gen preferred to be off. Not critical.
When timer reached its sub routine set up- all goes off.
Sub routine 2: This stage kips moisture out until main switch is off or reset. maualy.
Blower cycles for 2 min very 15 min.
Damper energized together. with blower on.
damper denergzed when blower off.
I would like to have the option to have the smoke generator cycles on and off every hr for for 20 min.
It has manual shut off too so in case I don’t need it it wont come on.
For the rest of the questions:
1) Blower is on most of the time.
2) There is a toggle off spdt. To start –Off-manual.
3) As far as my Knowledge goes an n.o condition is at deenrgized state. It does not have to Energize it could go to a cr. I need a make or break.
4) I am working on the text description and will post it soon.

Thank you, very much.
Hanan.