DeviceNet Scanner Module 1747 ??

Hi, I was wondering if somebody could help. We have just bought a DeviceNet Scanner Module 1747 to attach to an Allen Bradley 5/05 rack (we have never used DeviceNet before). We plan to attach 3 Drive motors to this Master Module and I know that we can do this with RSNetWorx. However, from a programming point of view in the processor how do I communicate with the I/O that has been Mapped from the RSNetWorx. Is it by M1\M0, block Transfer etc?

Wondering would anyone have advice, an example or know of a manual that would help on this. Appreciate any help. Thanks - Rpax

Using RSNetworx, you define (map) how each device will appear in the I/O map of the scanner. The scanner has 32 word of inputs and outputs, with one word each dedicated to control and status of the card.

RSNetworx communicates with the scanner through the SLC/backplane. You have to define a SDNPT device in RSLinx for RSNetworx to communicate with the scanner.

word zero of the output image table is reserved for the scanner module command

Since you've never used DeviceNet before, you're going to need a good overview of the basics; power supplies, wiring, termination resistors, and the role of RSNetworx software in configuring scanners and slave devices.

There is a woefully underused PowerPoint slideshow tutorial that is included with RSNetworx for DeviceNet software. Find it on the CD and watch it carefully.

Generally I strongly recommend having a 1770-KFD or 1784-PCD interface to the DeviceNet network. The passthrough drivers for the SLC platform are too tricky and slow for most novices.

Also, the 1747-SDN Installation Instructions have a very good overview of the data structure of the scanner module. Download and read carefully:

http://literature.rockwellautomation.com/idc/groups/literature/documents/in/1747-in058_-en-p.pdf

Also, can you describe the motor drives you are connecting to the DeviceNet ?

Hi, firstly many thanks for your replies. The DeviceNet Card that I am using is an Telemecanique Altivar71 VW3 A3 309 Card. I'll read this manuals and powerpoint at the weekend and see if were to go from there. Hopefully I can be a bit more specific with questions. I actually have borrowed a 1770-KFD to serial interface for this project so this will avoid going through the backplate.

In my ladder program do I simply turn the bits on and off and write to the particular words that have been mapped? or do I then need to send these to the scanner using a specific command. Again thansk for the help - Rpax

RPax said:

Hi, firstly many thanks for your replies. The DeviceNet Card that I am using is an Telemecanique Altivar71 VW3 A3 309 Card. I'll read this manuals and powerpoint at the weekend and see if were to go from there. Hopefully I can be a bit more specific with questions. I actually have borrowed a 1770-KFD to serial interface for this project so this will avoid going through the backplate.

In my ladder program do I simply turn the bits on and off and write to the particular words that have been mapped? or do I then need to send these to the scanner using a specific command. Again thansk for the help - Rpax

Click to expand...

Normally writing to the bits or words is sufficient depending on how much info your drive supports for mapping. Sometimes you need to explicit message if you require losts of info.

Ken Roach said:

There is a woefully underused PowerPoint slideshow tutorial that is included with RSNetworx for DeviceNet software. Find it on the CD and watch it carefully.

Click to expand...

Oooohhhhhhhhhhhh! I did not know that! Thank you. I WILL check that out today for a project I'm doing.

504bloke said:

Normally writing to the bits or words is sufficient depending on how much info your drive supports for mapping. Sometimes you need to explicit message if you require losts of info.

Click to expand...

From reading the manuals there seems to be two ways of Uploading Input and downloading Output Data from the module to the SLC Processor. Theres the input image table and MI\MO file transfer. In deviceNetworx the mapping seems to be mapped to the input and output image ie I:1.1.0 etc and O:1.1.0 etc.

Do I simply write to these images and the rest takes care of itself? (i.e no need to use MI\MO transfer and mapping done to scanner automatically). My Drives are 4 bytes Input and 4 Output without the need for complex control i.e On\Off, frequency etc.
Thanks - RPAX

RPax said:

From reading the manuals there seems to be two ways of Uploading Input and downloading Output Data from the module to the SLC Processor. Theres the input image table and MI\MO file transfer. In deviceNetworx the mapping seems to be mapped to the input and output image ie I:1.1.0 etc and O:1.1.0 etc.

Do I simply write to these images and the rest takes care of itself? (i.e no need to use MI\MO transfer and mapping done to scanner automatically). My Drives are 4 bytes Input and 4 Output without the need for complex control i.e On\Off, frequency etc.
Thanks - RPAX

Click to expand...

Yes just write to the output images and read from the input images

What are the drives, do they come with a dnet guide ?

Hi, I've got to the stage where I can get the Altivar DeviceNet Cards talking to the Scanner (using the Communication Scanner Input and Output assembly object 8Input and 8 Output). Customer support from telemecanique siad that the control words i.e to start and stop reverse forward are from a standard format. Not sure DriveCom or something like that. (From the manual I know to start the drive you need to send a Hex F signal to the drive) Does this ring a bell of any certain standard??. Appreciate any feedback

Usually the device net cards come with some sort of a guide that will explain the purpose of the bits. ie if 4 bytes input and 4 bytes output we can probably assume that the first 2 bytes are either command or status bits and the last 2 bytes would be commanded speed or actual speed.
ie for the input to the drive structure there are 16 bits to command the drive. (bit 0 may be run fwd, bit 1 may be run reverse etc) What these bits do are dependant on the assembly that is being used. From memory the standard assemblys are usually 70 & 71 (may be 20,21) but this should be explained in the Devicenet card guide. (you nominate the assembly used) Using RSnetworx you should be able to go online to the drives and check all these parameters. Sorry for the ramblings but some of this is hard to explain in text.
Regards Alan

Thanks Alan for reply, no ramblings at all. I understand what your saying as I initially tried to use the 20,21 assemblies and the 70, 71 assemblies but couldn't get the cards to communicate with my scanner. Your right also that in the manual it gives the the command bits for these assemblies.

However, the only way that I can get the network to talk is to use the Communication Scanner Input/Output assembly option but unfortunetely it does give the control command bits for these. When I rang telemechanique they said it was some Drive standard commands?? but said they'd come back to me on this as disn't know off hand. If I get anything will post up. Thanks for help