PLC Noob with questions

Background: I have no prior experience programming PLC, but I did take some programming in college along with a circuits class, So I do know a little bit I guess.

I was given a project at work and basically what I need to do is the following:

We measure oil cleanliness with particle counters every minute of everyday. What I need to do is read in the oil cleanliness value to a PLC real time and then graph it. Every new value that is read in is added to the graph. My company uses Allen Bradley, so this needs to be done using RSLogix. Is this even possible? Is it complex?

Thanks in advanced!

If that is all you are doing and nothing more I would recommend instead some sort of PC based data collection reading the devices directly with a product like this

http://www.advantech.com/products/RS-485-I-O-Modules-ADAM-4000/sub_1-2MLKHT.aspx

That in combination with maybe Archie's Advanced HMI would probably be all you would require.

http://www.plctalk.net/qanda/showthread.php?t=42656

Since you are not "controlling" anything the PLC will be overkill. If all you really care about is graphing it the PLC will just be one more needless step between you and the data.

DamianInRochester said:

If that is all you are doing and nothing more I would recommend instead some sort of PC based data collection reading the devices directly with a product like this

http://www.advantech.com/products/RS-485-I-O-Modules-ADAM-4000/sub_1-2MLKHT.aspx

That in combination with maybe Archie's Advanced HMI would probably be all you would require.

http://www.plctalk.net/qanda/showthread.php?t=42656

Since you are not "controlling" anything the PLC will be overkill. If all you really care about is graphing it the PLC will just be one more needless step between you and the data.

Click to expand...

Thank you for your response. I failed to mention that I would like there to be buttons where you can start and stop to particle counter and also reset the graph. Can this still be done without a PLC?

Edit: Also, the particle counter measure a lot more data, but I am only specifically looking to graph 1 maybe two different data series on the same graph.

tactical said:

Thank you for your response. I failed to mention that I would like there to be buttons where you can start and stop to particle counter and also reset the graph. Can this still be done without a PLC?

Click to expand...

Absolutely. Although the more "control" you add to the system will sway the pendulum the other way as far cost effectiveness. The PLC is great for solving LOGIC. The more logic you have to solve the better off you are with a PLC. The more you are just reading data the better off you are just taking that data straight to where you are processing it. You can get remote digital IO modules the same as analog. My recommendation would be an ethernet based topolgy. Or, depending on your situation a wireless system might have benefit as well.

tactical said:

Edit: Also, the particle counter measure a lot more data, but I am only specifically looking to graph 1 maybe two different data series on the same graph.

Click to expand...

Most of the modules such as the one I linked to above come with several channels as a minimum. The number of signals you will be monitoring in your case probably won't be that big of a factor in the decision making process. More so, the speed at which you wish to sample each channel might be the more significant factor.

video

I watched and download form this video
http://www.youtube.com/watch?v=f_1VnFCYSlE

I want to follow but I don't known about software (in video 0:35s). Anyone can help me and guide software.

tactical said:

We measure oil cleanliness with particle counters every minute of everyday. What I need to do is read in the oil cleanliness value to a PLC real time and then graph it. Every new value that is read in is added to the graph.

Click to expand...

What type of signal can you get from the particle counter?

tactical said:

My company uses Allen Bradley, so this needs to be done using RSLogix.

Click to expand...

My choice would be their favorite model of Allen Bradley PLC or PAC and a Red Lion G3 HMI for very robust logging and graphing. Depending on the signal output from the particle counter, the G3 may even act as a gateway device, greatly simplifying the logic and programming.

Advantages: Permanence. Bulletproofedness. Uptime. Power interruption recover time. You get a quick 'fresher on PLC logic. No new hardware or software for the customer to learn or purchase.

Using a rolling queue in the PLC you can store a lot of process information in a PLC even if there is an interruption in the HMI or network data collection system.

Navigating a trend object on a G310 is as good as it gets for responsiveness and functionality, and you can do it via a network with a browser if you choose. It can make the task of logging the data a set intervals, with tags you can use to start and stop the trend, all very quickly with Crimson 3.0.

Disadvantages: initial cost.

tactical said:

1) Is this even possible?
2) Is it complex?
Thanks in advanced!

Click to expand...

1) Yes.
2) No.The logic to do this will probably be linked to, or built quickly here before you can procure a list of preferred hardware. It is not complex.

tactical said:

Thanks in advanced!

Click to expand...

You're welcome, and welcome to the forum.

The HMI is built on a PC platform. It will do almost all of the work of graphing. Graphing is a built-in function. Chose scale, color of pen, time interval.
That's why the PLC and RSLogix will do very little. All it has to do is get the value, scale it, and send it to the HMI to do the rest.
Start and Stop Particle Counter will be in PLC. When you're done, you will only have 5 or 6 rungs.
First step is to download software for the HMI and do a practice screen. After that, you'll know what you need, and how incredibly easy it is, because the HMI does all the work.
That's why Damian suggested a PC. You didn't even need a PLC until you said you wanted to start/stop the particle counter!
OkiePC laid it out pretty well. We need to know the model number of the particle counter to help further. Is budget a concern? You're locked in to Allen Bradley for the PLC. Do you have a choice for HMI?

sighs said:

I watched and download form this video
http://www.youtube.com/watch?v=f_1VnFCYSlE

I want to follow but I don't known about software (in video 0:35s). Anyone can help me and guide software.

Click to expand...

welcome to the site.
Please post seperately to other posts.
your answer-
1. Step7 - siemens programming software - about $2~4,000
2. Kepware - available free

Wow, thanks for the responses everyone! Hope you had a good thanksgiving

OkiePC said:

What type of signal can you get from the particle counter?



My choice would be their favorite model of Allen Bradley PLC or PAC and a Red Lion G3 HMI for very robust logging and graphing. Depending on the signal output from the particle counter, the G3 may even act as a gateway device, greatly simplifying the logic and programming.

Advantages: Permanence. Bulletproofedness. Uptime. Power interruption recover time. You get a quick 'fresher on PLC logic. No new hardware or software for the customer to learn or purchase.

Using a rolling queue in the PLC you can store a lot of process information in a PLC even if there is an interruption in the HMI or network data collection system.

Navigating a trend object on a G310 is as good as it gets for responsiveness and functionality, and you can do it via a network with a browser if you choose. It can make the task of logging the data a set intervals, with tags you can use to start and stop the trend, all very quickly with Crimson 3.0.

Disadvantages: initial cost.


1) Yes.
2) No.The logic to do this will probably be linked to, or built quickly here before you can procure a list of preferred hardware. It is not complex.


You're welcome, and welcome to the forum.

Click to expand...

Im not sure what you mean by the type of signal?

Im not sure what you mean by the type of signal?

Click to expand...

Process signals are divided into several basic types. The very most basic are analog (coninuously varying over a Min-Max range) and digital (on or off). In the analog category, there are farther subdivisions, including DC voltage (0 to 10 volts or 0 to 5 volts), current (4 to 20 miliamps), or milivolts (thermocouple temperature signals).

Each digital signal can be operating at different voltage levels, from 24 volts DC to 240 volts AC.

Is this a BS&W application? Pipeline or custody transfer? Refinery? Just want to measure life of oil in equipment? Just wondering.