Flat or round?

S

Thread Starter

simon walker

I am moving to devicenet and considering the cabling. Distance is not a problem as the longest distance is only about 300ft. I like the idea of the flat cabling and vampire connectors. Is there a limit to how many vampires I put on there, for example, if I prewire my conveyors I could simply snap them together on site. The alternative is the large cabling with the big connectors. I am not sure about prices yet either.

I can not find modulating valves on devicenet either or a 4-20mA output. I could use flex but I am making a statement and would prefer to use all devicenet.

Last but not least, what is the best way to talk between an ethernet network and existing DH+ (not a lot of data)?

Thanx
 
R

R.A. Hulsebos

Hi all,
I have mentioned this before, but since some
questions for information on this list show
that not everyone has seen it: i d like to
recommend my site at
http://ourworld.cs.com/rahulseboswhich lists more than 400 fieldbus systems,
90+ books, user groups, etc. all about
fieldbus systems and industrial networks.
Apart from the Compuserve banner :-( there
is no commercial info on my site. So enjoy!

Rob Hulsebos
[email protected]

 
R
Burkert makes modulating valves that work on DeviceNet. Go to www.burkert.com. Omron makes a DRT1-DA02 Analogue output module. 2 outputs
that can be configured for 4-20 mA. This is the only stand alone module I have found. There are other vendors such as Beckhoff that sell DeviceNet
communication module that can be used with numerous types of I/O. Check out the ODVA website.


Roy Speers AScT
Control Specialist
Molson Canada
 
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Steve Godfrey

For DeviceNet wiring, I have found that flat is much easier to wire and there is no limit to how many vampires you can put on. Check for both prices with your vendor and weight the pricing with ease of wiring.

To look for modulating valve go to ODVA.org, they have a full list of DeviceNet compliant devices.

As for DH+ to EtherNet, the easiest way is through a ControlLogix gateway. All you need is a rack, power supply, an EtherNet card and a DH/RIO card.

Steve Godfrey A.Sc.T
Process Technologist
Weyerhaeuser Canada
 
R
Yes but be aware that the 1756 DHRIO card only supports 56k Baudrate. I got caught on this one and Rockwell has not come back with an answer why the new Controllogix platform even being a later product does not support all DH+ baudrates.

Cheers Rolf
______________________________________
Rolf Gerste
PRISMA Automation Pty Ltd
PO Box 35867
Winnellie NT 0821
Australia
Phone 08-8984 4385
Mobile 0417 837 933
Fax 08-8984 4001
mailto:[email protected]
http://www.prisma.com.au
ACN 097 718 342

 
M

Marshall, Philip

Have you considered AS-I? It is a flat cable vampire technology that has both pneumatic valves and 4-20mA output modules available from several
vendors. It is not as sophisticated as DeviceNet but for conveyors it is usually good enough according to our conveyor OEM's. Wiring is "free form" as long as its less then 100 meters of cable and has no minimum distances between nodes or terminating resistors so it can be significantly easier to use. Typically it is significantly less expensive then DeviceNet if you
don't need DeviceNet's functionality.

There are many gateways available as well including DH+, Profibus, DeviceNet, Ethernet, etc.

Phil Marshall
Siemens Energy & Automation, Inc.



 
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