DH+ Converter/Conversion


Thread Starter

Kirk S. Hegwood

Hi Everyone,
We have a number of legacy control systems that are interconnected via Allen
Bradley's DH+. Our goal is to migrate these systems and new systems to a
more "open" system, preferably Ethernet, and commingling the PLC's and PC
control. Any suggestions and/or manufacturers that have gateways to convert
the DH+ protocol without having to use RSView or other Allen Bradley
products? We want to keep it "open".

Thanks in advance for the help.


Kirk S. Hegwood
Signing for Hegwood Electric Service, Inc.
[email protected]


I did this to a couple of lines at a previous employer. My situation was
Dh-485 tho. I found the best way to do it was to replace one of the SLC's
that was not performing any difficult tasks (typically it wound up boeing a
conveyor controller) with a SLC 5/05. the 5/05 is the one with an Ethernet
Jack. The replaced processor simply went back to spare parts inventory.

Then, I added logic in the 5/05 to gather data from the other machines
using the existing network, and consolidate it in the 5/05 memory.

Finally, an ActiveX from Automated Solutions would bring the data from the
5/05 into my VB app that I had written. A.S. has a fairly liberal
licensing policy, in that you buy the development license, and you can
distribute the run time with no royalty.

From there, it was a quick trip into the DB and onto the intranet web pages
for display to all....

I would suggest something similar, only (obviously) using a plc that could
talk DH+ and ethernet. Not sure which model would work for that, tho, as I
haven't had much call for DH+ beyond a SLC 5/04.


--Joe Jansen
If you take this approach, use a PLC5/20E or 5/40E, or if you really need it you can even use the 5/60E. All talk ethernet. Better would be to use a contol logix box (thats the AB 5550 line). It ties DH+, DH485, ethernet, controlnet, devicenet, serial all together with minimal pain.
Dear sir,
in my idea you can go 2 way,
1. using software for DH+ drivers, from software toolbox web site or other opc driver that can support DH+ protocal (www.opcfoundation.org).
2.using hardware based communication gateway sush as X-link from SST technology, but for this solution not flexible than software driver.

Geoff Nunan Advanced Integration Pty Ltd

Allen Bradley Control Logix Gateway.

Buy a backplane, drop in a 1756-DH+RIO card
and a 1756-ENET card, Each card is a converter to Control Net (Open) which the backplane uses to communicate between the cards.

Very simple.