AB Ultra3000i with DeviceNet

Hello,
We have a project we are working on here at the plant. 2 AB Ultra3000i with devicenet, SLC500 5/03 with devicenet scanner. I read the Ultra3000i manual about devicenet and its a head scratcher. I set up the drive for my motors and auto tuned them already, but I believe I need DEM instruction to explicit message the drive from PLC. But can someone shed some light on the subject?
My backup plan is using I/O, but I wanting to try devicenet as much as possible I am very weak at devicenet and want to use this as a learning experience.

The machine we are trying to build is a 2 axis parts loader. Z and Y axis, I would like to be able to change the parameter for both axis when the machine changes to a different part.

Thanks for any help.

anyone?

Its probably been ten years since I last dealt with a SLC-SDN-Ultra3000i combo. I'll look in my archives and see what I did and if I find it I'll pass the project over to you for reference as I know that machine was at the GM-Ypsilanti Transmission plant and I believe is now in India.

BigDollaBill1234 said:

anyone?

Click to expand...

I found the SLC file but its not very useful without the SDN configuration and Ultraware project files. I believe it I have them on an old laptop at home, I'll look for them this evening if you're interested.

Wonderful, thank you very much. We are about 10 minutes from the old Willow Run plant that my father worked at for 20 years....small world, thanks again.

About 5 years ago I did a big project with a SLC and a bunch of Ultra 3000's over Devicenet. This was my first exposure to Devicenet and it's getting a bit hazy but I can give you a few pointers. I assume you have RSNetworx software? You will need this to set up the network. The biggest thing I remember is that you want to use I/O Messaging instead of Explicit Messaging with the drives if at all possible. I/O Messaging allows you to set a block of bits and words in the SLC that control and monitor the drive, just like if you had hardwired I/O. You select specific input and output "assemblies" that have the functions you need for your application, and configure them in RSNetworx. (See the Assembly Object section in chapter 2 of the Ultra 3000 Devicenet manual.)

I should add that, in my experience, Devicenet is pretty bulletproof if set up correctly. We have a number of Dnet installations in our facility and I can only think of a few instances in 15 years where we've ever had to troubleshoot network related issues.

Can you elaborate alittle more on the I/O messaging. I was trying to figure out how MSG instruction works on RS500 but got stuck. Thanks.

With your average I/O block type device, the IO transferred across DeviceNet is pretty simple; a few bytes for the input data, a few bytes for the output data.

With your average VFD, it's simple too: a Word for the Command bits and a Word for the Speed Reference on the output side, and a Word for the Status bits and a Word for the Speed Feedback on the Input side.

Those collections of bits and words are called an "Assembly" in the DeviceNet world.

The Ultra 3000i has several pre-defined Assemblies you can choose, or you can choose a complex user-configurable Assembly.

Each word of the assembly points to a different Parameter in the motion controller. It's a build-your-own-sandwich approach to defining the I/O data that's exchanged between the SLC-500 and the Ultra 3000i.

If the Assemblies don't carry all the data you want to change over in between parts, you have to use some explicit messaging; that's where the DEM instruction comes in.

Furthermore the Ultra 3000i gives you a special IO-based way to access parameters using a pointer.

So let's take a step back and see what kind of information you want to exchange between the SLC-500 and the Ultra 3000i.

Thanks for everyones help, it is becoming alittle more clear....

I want to be able to , enable, start, stop, select presets ( jobs ) and status thru devicenet. I know I can probably do all of that threw the I/O plug, CN1... but I want to get better at devicenet so really I want to be able to do as much as possible with the drives....but baby steps now.

Unfortunately we cannot use DEM instructions due to firmware on our 5/03

"I/O Messaging" is a DeviceNet term; it has nothing to do with the MSG instruction in the PLC. Actually, on the PLC side of things, you don't need any special logic at all. I've attached a few screenshots from RSNetWorx that may help. The first shows the Properties window of an Ultra 3000 node. You need to set the proper Assembly Instances based on which bits you want to access in the drive. (These are spelled out in the Devicenet manual which I assume you have... you won't get far without it.) This dictates which data will be transferred back and forth between the drive and the SDN scanner. The second pic shows the Properties of the scanner module itself. Here you control where that data ends up in the M File of the scanner. These M File addresses can then be used in your PLC program. For example, M1:1.47/0 is the "At Home" signal for this particular drive which can be used in an XIC or XIO contact. If you click the Memory popup menu and change it from M File to Discrete, you can assign actual PLC 'I' or 'O' addresses to the data and bypass the M File. (However, it only allows 32 words of input and output to be assigned in this manner, which get used up quick, so I had to use the M File for my drives.)

Don't expect to get this figured out overnight. It took me weeks with the hardware in front of me just to get a handle on it, and then even more time to decide how I wanted to organize the data.

We have RSNetworx for DeviceNet, Ultraware, and RS500 software.

That exactly where we are at right now with the RsNetworx...thanks for the screen shots... I will do more reading on the assembly instances....

The M file is a hang up for me... Never seen it before... I used it in RsNetworx... but got lost in the PLC...where is it on rs500? Im guessing Discrete would work for my application, and sounds abit easier. So once I change the addressing in RsNetworx back to discrete and use automap, then I need to figure out the assembly instances....

It's better to use Discrete instead of the M File if you can. The main reason is that every access of the M File takes a certain number of milliseconds and it can really slow down your scan time. The workaround is to do a COPy of the entire M File to binary files at the beginning (inputs) and end (outputs) of your program.

You can address the M File just like regular I/O. If your SDN module is in Slot 1, valid bit addresses would be M0:1.0/0 (for outputs) and M1:1.0/0 (for inputs).

Stick with Discrete if at all possible.