AB Simple DeviceNet addressing question?

uptown47

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Hi all,

I have an allen bradley PLC (5/03 CPU) the 1st card is a devicenet card with 32 words inputs and 32 words outputs.

I'm a complete newbie to AB so bear that in mind when reading and responding to this question.. ;)

I need a couple of inputs at one of the nodes. There are no inputs free but a full output card (i.e. 4 bits) is free. Can I just take out the output card and swap it with an input card?

If so.. are the addresses created the same as the Output addresses but just with an I in front of them. ie.

Output card has O:1.11/0 - O:1.11/3

I swap it with an input card do they become..

I:1.11/0 - I:1.11/3

??

I've only used AB a couple of times in the past and I've never used DeviceNet before so any help/pointers will be most appreciated.

Many thanks

:site:
 
You need to get the software called RsNetworks for DeviceNet.
That will allow you to setup your nodes the way that you want them...
ONLY then can you start to even think about "changing" cards.

Rule of thumb: If you don't know, don't touch it until someone that does know can help.
 
Can you access your PLC with an Ethernet connection?
If so, you just need to access the software to re-configure your DNT file appropriately.

If you cannot connect ethernet-wise, you will have to buy the specific cable required to connect directly to the DeviceNet Scanner Card.
Do you have a DNT file for the system that is currently in place?

The Node that you are speaking about, replacing the card, can you give us a vendor p/n or anything? Is it like Beckhoff I/O or something?

There are some tutorials that can help you a little on the web...
http://www.bin95.com/DeviceNet_Industrial_Network.htm
http://literature.rockwellautomation.com/idc/groups/literature/documents/gr/dnet-gr001_-en-e.pdf
 
Last edited:
Hi,

The module is a 1734 ADN DeviceNet Point IO
http://www.odva.org/tabid/151/ctl/Detail/mid/512/xmid/17334/xmfid/7/Default.aspx

The output card is a 1734 OB4E and I want to replace it with a 1734 IB4 (input card)

The 1734 ADN IO Module says that it supports "Automatic Configuration" does that mean there's a way to tell it to 'read' what modules are attached?

I'm not sure what a DNT file is. I have the RSS file..?

I can't connect via ethernet to the PLC it only has a RS485 port on it.

Do you know what cable I need to get?

Thanks for the links to the manuals I'll have a look through them.

Cheers

:)
 
The RS 485 connection will need a 1747-UIC converter if you only have USB
if you have a serial port then you can use the 1747-Pico module for the RS 485 conversion in both cases you ned a 747-cp3 cable
 
It has been a while since I have messed with devicenet on a SLC.

But if you are new to this you will probably want to play with a spare first before trying in the real world.

To get on the devicenet network you will have to map a driver in RS Linx. Then you will have to open RS Networx for devicenet. In the setup properties you will have to specify which driver to use. Scanning the network and uploading, then saving the configuration is the next thing to do.

If I remember correctly, the 1734, treats it I/O as beeing on another devicenet network. Therefore you will also have to scan that network and map it as well. Instead of replacing the I/O module it would be much easier to add it, since you don't know how the previous person has mapped the I/O.

Devicenet is a bit oriented protocol, so you have to tell it where you want everything to be, then you have to remember what you told it when writing your program.

Swapping a module on any network, except maybe ethernet is not as simple as swapping a card in the main rack.

I would recommend looking at the manual for a 22 COMM D which is the manual for a PF 40 drive comm module to get a good understanding of how devicenet works. Then get the devicenet manual for the 1734 and play a little bit before trying to put in a real world application.

GOOD LUCK
 
Thanks for the advice.

Unfortunately I haven't got access to a testrig to do any testing.

I have electrical drawings so I know how the original IO was mapped.

Does anyone know what lead I need in order to talk to the devicenet module?
Is it the 1747-UIC lead that I use to program the PLC or something different?

Many thanks for your continued support.
 
not positive on the devicenet the 1747-uic is a rs 485 converter only so if the devicenet is an rs 485 port then yes you will probably need the converter. The correct cable should be listed in the manual for the devicenet module usually listed in the communication chapter you should be able to download that manual from the rockwell knowledge base. Yor looking for the programming manual

http://literature.rockwellautomation.com/idc/groups/literature/documents/um/dnet-um004_-en-p.pdf

page 48 of the manual has the cables options you need however it looks like yo can also do a passthrough connection from the SLC someone may correct me on this as I've never used this module
 
Mordred


Thanks for your help. I'm going to have a go and see if I can communicate with it. Failing that I'm just going to electrically wire the signals back to the main PLC.

Thanks for all the help.

;)
 

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