A new System

[Tim R]

Hey everyone,

Ok, your ideas are all pretty good. A couple of things here that I may have been vauge on.

1)The machines feeding the Fill Stations are fixed. The part made on each machine changes. Each Fill Station can be used at any machine.

2)The function of each Fill Station is the same for each machine. The data written to the RFID is a variable.

3)When a box is filled, I will receive a done bit from the machine and send the box onto a trunkline conveyor.

4)The HMI Station will need to create and send the data to the RFID. (I will make a form on the HMI to create work orders).

5)The boxes will terminate at a common location where the tags will be read and displayed on the HMI. The SCADA system will log and save the data.

Jesper, by looking at your layout, you have the HMI talking directly to the PLC. Ok, that's no trick. Are you suggesting then that the PLC will translate the RFID info and direct it to the right write head? Or am I missing something here? There is no local HMI. No need for one.

I haven't ruled out wireless. Lets just say it's impractical.

Terry, I guess it would depend on your definition of high speed is. I could (theroretically) have 13 boxes waiting for data to be written to their tags and transfer onto the trunkline.

The system I am proposing would need to be able to understand that when I move one fill station to another machine, it's RFID address and PLC address stay consistant with the information being sent from the HMI. Now if I give every Fill station a unique address, then the operator will need to know that fill station #5 is now on machine #12 so he can make sure the RFID info is valid. This is what I'm trying to avoid. The less the operator needs to think about what is where, the easier it will be to set up the system.

Now Profibus and devicenet, in a trunkline type setup will work as described. But I think so will Canbus. (If distance isn't a factor). And Canbus would be a lot less expensive. I'll be going over hardware with my vendors next week. I'll tell you where I end up and let you guys shot holes in it.

Hey Norm, I just talked with Chris. We'll be in touch after you get back. Have fun.

Tim R

 

[Tim R]

One other thing. As far as the question "what does the RS Stand for. recommended Standard is correct.

But I would also accept Rockwell Software, Radio Shack and Really Sucks.

Random Solution is really funny as well.

Anyone Know what OPC stands for?
Tim R

 

[RMA]

Anyone Know what OPC stands for?

OPC stands for OLE for Process Control. This is a further development of the Microsoft OLE standard (Object Linking and Embedding) for Data Exchange under Windows, addapted for the specific requirements of Process Control.

 

[ndzied1]

Thanks Tim,

I'll try to have fun. Half of my absence shold be fun but the rest will be made up for it in spades.

 

[Terry Woods]

OPC stands for "Other People's Cigarettes".

BTW Tim, that wasn't me asking about speed... that was Jesper.

I was asking about the nature of the layout.

 

[akreel]

OPC stands for "Other People's Cigarettes".

I like that!

I found my "final answer" on the TIA website. They WROTE the standard, people. I'm sticking with it. It makes for better ****tail party conversation, anyway.
http://www.tiaonline.org/resources/acronym_results.cfm?keyword=r

RS Radiocommunication Sector (of the ITU. Replaces CCIR)

 

[Terry Woods]

So... if you have been a good boy and things are easier than they usually are...

You could roll your station up to any of the valid locations and simply "plug-in" to a connector (one located at each valid work place) and then turn on the machine. The boot process would include a "Hello, I'm here!" to the central processor... a little hand-shaking between the station and the central processor, and then the station would get the "OK to Go" sign.

At any time, you should be able to send a "Log-Off Request" to the central processor... the central processor would ask for any remaining data that might need to be transferred (a little house cleaning before log-off), and then send an "OK to Disconnect" signal.

I use a TI-WAY Network with my TI Systems... all of the above can happen without breaking the network and actually, I can disconnect any local station without requesting the log-off. I can disconnect any time I want and the network remains.

Some networks won't tolerate that kind of behavior at all... "Everyone has to be in or no one is in!"

The network manager is always checking to see that the network is intact... if someone doesn't answer-up then there is hell to pay!

Some networks don't mind too much if a local station "fails" (disconnected or otherwise). In some cases, the local station can reconnect and all is forgiven... in others, the local station is not allowed back onto the network unless the manager goes down and reboots to re-establishes the network.

The (B)itch is that the manager is watching everything from a very narrow perspective.

Seems like there ought to be a way to fool that old man(ager)...

Hmmm... each station has a unique ID on the network...
That unique ID has to be present and there can't be two stations with the same ID... or can there?

How about a "Dummy Station"... This station exists in software only... it's not real. When a station requests a log-off, maybe the dummy station can be assigned the ID of the station going off-line...

Hmmm... this sounds like a situation where that special Network Code Language comes into play...

We all have seen that network operation seems to pretty damned closed to outside intervention... however, as I recall, each network has a variety of special function codes that can be exercised to manipulate the operation of the network...

Essentially, the network is maintained with a full complement of stations... real or otherwise (dummies). This means that the network can continue operating with as many a full complement of real stations to a full complement of dummy stations.

Just a thought... I haven't done this but it seems it ought to be do-able.

In the absolute worst-case... you could communicate over 8 digital lines from each potential station using ASCII code.

 

[dandrade]

Network chart definitions http://www.synergetic.com/slidechart.htm

It project involves multiples "sincro" operations. Interesting, if expose a picture graphic it help will be better.

CanBus aproval, similar project.

 

[JesperMP]

Jesper, by looking at your layout, you have the HMI talking directly to the PLC. Ok, that's no trick. ... There is no local HMI. No need for one.

OK, because I know so little about your application I just "filled in" a local HMI because it could be useful and because it is possible.

..Are you suggesting then that the PLC will translate the RFID info and direct it to the right write head? Or am I missing something here?..

Yes, with the RFID units on Profibus or DeviceNet the PLC would access these units directly.